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Forcefield Back Protector Pro Sub 4
  • Forcefield Back Protector Pro Sub 4
  • Forcefield Back Protector Pro Sub 4
  • Forcefield Back Protector Pro Sub 4
  • Forcefield Back Protector Pro Sub 4
  • Forcefield Back Protector Pro Sub 4
  • Forcefield Back Protector Pro Sub 4

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Forcefield Back Protector Pro Sub 4 Videos

Forcefield Back Protector Pro Sub 4

The Forcefield Back Protector Pro Sub 4 is the worlds first Motorcycle back protector to transmit less than 4kn when subjected to the standard CE test.

The Pro Sub 4 has been specifically designed to test at under 4kn when subjected to the standard CE test EN1621-2. Independent testing by SATRA shows a mean test result of 3.38kn transmitted energy, making it the first motorcycle back protector in the world to attain this level of performance. Constructed with a removable and washable outer cover to give the rider the ability to keep the back protector clean and hygenic, it also makes the protector more flexible as it is not bonded at the edges, this in turn makes it more comfortable to wear, a prime consideration in the design process of any Forcefield product. As with all Forcefield Body Armour® the Pro Sub 4 has RPT (Repeat Performance Technology) ensuring continued and consistent protection even after multiple impacts. 


  • The World's first Motorcycle back protector to transmit less than 4kn when subjected to the CE test EN1621-2 (Level 2)
  • Removable and washable outer cover
  • CE Level 2 Rated Protection
  • RPT (Repeat Performance Technology)
  • Comfortable and non restrictive
  • Flexible
  • Breathable
  • Moulds to body shape
  • Adjustable waist and shoulder straps
  • Multi Sport use

Read more about this product in this WebBikeWorld.com Review

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Forcefield Back Protector Pro Sub 4 4.7 5 46 46
Doesnt get any better than this! I wear this under my riding jacket. It has superior protection across the entire back including the tail bone. Forcefield says it can absorb impact after impact without destroying its durability, unlike hard shell protectors. Initially it feels like you've strapped a stiff board to your spine but after only a couple hours it forms nicely to your back shape. Apart from the kidney belt holding my core (which can be loosened or tightened on preference) i would never even know im wearing it. The outer case is easy to take off and wash (cold water + air dry). Which you'll be thankful for after wearing it on a few hot summer days under a suit or jacket. The only draw back is it must be worn under a suit or jacket, unlike other protectors which have hard plastic plates to absorb road contact directly. April 12, 2014
Claimed to be the best - hope I don't need it! Overall, the back protector is very nice. Fits well and easily conforms to your back, especially when warm. It's thin enough to fit under most leather suits, so no adjustments required. My only gripe, which might come down to sizing, is that it rides up my back a bit when donning the suit. Coverage remains good, but combined with my helmet and the leather suit's speed hump, my neck's range of motion is somewhat impacted. I recommend wearing the gear you plan to use with the back protector, getting on the bike, and trying your typical body positions. Have a helper measure your back while in position - should ensure you don't limit your range of motion. March 17, 2014
Padded Courage I am 6ft 165 and ordered the size MD. It's a bit snug under my Astars Tech 1 jacket size 50, but perfect under my size 52 Puma track leathers. It does feel a bit bulky and stiff right out of the packaging, but molds to the contours of your back really well once it's on under your leathers. Comfortable while riding. Haven't needed to test the impact absorption yet, but it does provided a bit of additional padded courage. March 15, 2014
need protection? he is the final stop ,if you looking for best back protector you can buy -super comfy ,after 3-5 min of wearing ,like a your thick skin) -super protected February 17, 2014
Great product, great protection When the product arrived I was afraid it was a touch too large although I had followed the measurements to the letter. It turned out it is large by design (and it should be tucked in your pants) as it covers the whole tail bone. It is not cheap, but it is definitely worth it in terms of protection. It does take a little to get used to it under the pants, but again, this is not asking too much to ride with a sub 4kN back protector. Definitely recommended. February 3, 2014
goes under denim jacket on cruiser smoothly I don't have a bullet bike, I use the back protector on my cruiser, a Honda Shadow. Traffic can get crazy and I wanted a little something extra just in case. The back protector is super comfortable, easy to put on or take off, and fits well. Adjustable, and the armor itself molds to the back, and I wear it under my denim jackets. My jackets aren't skin tight, but with a jacket over the protector it does get noticeably tighter, but I can still close up the jacket and move comfortably. You really don't notice it after a while. I think the best part is just how it molds to the back and fits under normal clothes. If you wear hipster super skinny slim fit clothes, it's not going to work. Also, if you're a hipster, I want to punch you in the face. Anyways... My only complaint is I think the straps could be a little bit better made. They aren't flimsy, but doesn't match the high quality of the protector itself. I'm happy with the product, it's really easy to wear, not a hassle at all, and if you're going to protect your back, get the best. January 21, 2014
Well worth it This back protector is well worth the money. The best protection is the one you will actually ware. This takes seconds to put on under your jacket and when you put it on after a few moments you forget that you are even wearing it. While I have not crashed in it the level of protection it offers looks very to be very good. As far as fitment goes I am 5'11'' and 240 lb. and I got a large. It fits me perfectly. October 14, 2013
Great, protective back protector Great, protective piece of gear; I've upgraded the armour in my leathers and my back protector to the Forcefield gear. It /is/ thicker than many other choices, which may be an issue in tightfitting leathers. The thickness (outside the leathers) goes away when riding; on-track I barely notice it. I've worn it on super-hot NM track days, and it's been fine from a cooling perspective. Not thje cheapest back protector out there, but I've spent too much money buying the three cheapest instead of the best one. October 14, 2013
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Have a functionality, fit, or otherwise product-specific question about the Forcefield Back Protector Pro Sub 4? Ask it here! If you have a customer service or shipping question, please direct it to our Customer Service department.

Forcefield Back Protector Pro Sub 4
Already Asked: 4 Questions, 35 Answers
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RevZilla Store asked: Why did you choose this?
Sunbir W: After a lot of research, found this to offer the best protection that is available in the market for the back and spine Apr 15, 2014
Justin R: Best protection Apr 12, 2014
"" ": Safest back protector on the market Feb 16, 2014
JUAN R: It´s suposed to be the best back protector. Feb 14, 2014
Jeff R: It's the best body armor made! Since you carry almost all of the Forcefield line of products, may I recommend that you take a look at carrying just a few of their other items for snow sports too? I am talking about the Board Shorts (tinyurl . com/kknpfgt), Knee Protectors (tinyurl . com/lrqhxz7), and Boom Shorts (tinyurl . com/omdsz83). Trust me. There's a market for it. I had to order shorts and knee guards from England, but would rather have paid you! Thanks! Dec 31, 2013
Mark M: Had a wreck & broke my back in 4 places. I was wearing a jacket with a CE approved spine protector. Had I been wearing this I would not have spent six weeks in hospital & not have had to learn to walk all over again. This is CHEAP INSURANCE! It is also comfortable & you forget you are wearing it. Don't be so COOL it kills you. Dec 17, 2013
Wade S: Reviews. Oct 26, 2013
John L: How could I not choose Forcefield for my spine protection. All it takes is for one fall and without the proper protection and you just can't take it back, This product screams safety fits well right out of the box, I highly support all forcefield for making the best safety products on the market. Oct 2, 2013
Athena M: I love Forcefield and did a lot of research before purchasing this. It is quite thick but very light and comfortable. Great protection but too thick under the tight fitting kangaroo suit, switched to the ladies Pro Sub 4 (which was not available when I purchased this). Sep 26, 2013
Tim F asked: Hey. I'm just under of 5 11", 32" waist, 178lbs. I took the torso measurment as advised by forcefield and keep coming up 21-22". I'm usually a medium in everything and the 22" puts me into an XL. Would you think the L would do it? thanks. tim Aug 18, 2013
Answer this · Send to friends Good question? Yes (0) No (0)
Mary R: I'm not sure why this thing says my name is Mary, but whatever. I'm personally 5'9", 160 lbs, and about a 31 inch waist and I ordered a medium and it fits but it may be a hair too small. But it's so close that a large would have been too long. Best thing I can tell you to do is order a large because that should work for you as put it on with the gear you plan to wear with it, helmet too. The back protector should cover your tailbone with the tip, all the way up to your neck pretty much. Should be about an inch of space between the top of the back protector and your helmet. Make sure it's not bunched up or caught on your gear too as that would give you an inaccurate idea of how it fits. If its too short, go up to an XL if its way too long (doubtful) go down a size. Most likely though, I'd guess a large would do you. But it's worth it to send it back if its not right because the more uncomfortable it is, the more likely you are to not wear it or become distracted while riding. Hope that helps! Aug 19, 2013
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Kenneth H: Hi! I have had one for sometime now and use it always! Even when above 100 degrees - live in Yuma!

The medium is fine for me. I am 68 to 69 inchs tall.
The waist has lots of adjustment and that should not be a problem also.

I would guess the large would work fine for you. You can try it and if do not like the fit. I am sure RevZilla will change it out.

I have not tested it effectiveness and hope never to but I will not ride without it on.

Yuma, AZ
Aug 19, 2013
Reply to Kenneth Good answer? Yes (0) No (0)
Michael C: Hi Tim, don't know if large or extra will work best. I bought one earlier this year for racing and bought an extra large. I'm 6'1, 180 pounds, and have a 32 to 34 waist. I have an athletic build. Works under my leathers great. Would buy again if ever needed. Excellent product. Hope this helps some. Good luck. Mike Aug 21, 2013
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James H: Tim, I couldn't tell you for sure. Bought mine for racing last year and honestly never had a chance to try it. Sorry couldn't help you out. Anthony's reviews are usually very helpful in making decisions on size. Plus, their return policy is awesome if you are not satisfied. Aug 20, 2013
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Peter CStaff: Hey Tim. Yes, I think the L would do it for you. I'm 6', 34" waist, 195lb and bought the XL based on their measurements. I think I'm going to actually sell the one I got and buy get the L when I have a chance. Hope that helps! Aug 19, 2013
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Mike B: Hey Tim,
I'm 6" and just shy of 215 pounds. I wear a large and it covers my spine just perfectly. I think the Large would suit you too and the XL would be too much. Hope that helps.
Sep 1, 2013
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manuel s: Hi Tim,

I'm 5'9" 180 lbs. I got the Large and it thinks it's a bit long. Wish I would have ordered the medium. Hope that is of help.
Aug 19, 2013
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Kenneth H: Hi! On my response the other day! Forgot! Torso measurments is the most important. Want max back coverage possible.

Aug 20, 2013
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Gregory B: I think so. The protector belts are adjustable. It is plenty long, extending well over the tailbone, so I don't think you would end up short. Aug 19, 2013
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Maria M: My husband is 5"10' 180lbs and large is too big for him. I think medium would be a perfect fit.. Aug 19, 2013
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Robert M: I'm 6'1"/205 w/a 46" chest and have a large. IMHO the large would be to big for you. Aug 19, 2013
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Nikolay K: I am 6'3 and the xl fits me perfect, so if you are 5'11 i would go with the L Aug 19, 2013
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Michael G: you'll be fine ... Excellent choice by the wat... Aug 19, 2013
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A shopper asked: Hi guys,

Looking at the Pro Sub 4, trying to determin the right size.
I am 5'11" or 6 foot depending on the day and the ruler, I am thin though which affects the waste straps. 34" waist. According to the size chart I would probably be at the edge of medium and the beginning of large. My instinct is to go for the longer large but I am concerned the straps will be too stout.
What do ya' think?

Jul 15, 2011
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med23: I am 6'2" and 210 pounds. I use the large ProSub4 and it is perfect. I would think that the medium might be better for your height and thin build as you described. My only reservation would be if you have a very long torso...in which case you might need the extra length of the large. The straps on the large also might give you too much material and be a bit sloppy under your suit. They gave a lot of material for a huge spectrum of torsos, which you don't need to worry about. Go Medium...and Revzilla is amazing at return/exchanges so you can't go wrong. Jul 16, 2011
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Mike37: Adam,

I am 5'10" about 180 lbs with a 32" waist and I got the large. It actually was barely a bit to big for me but the straps have tons of velcro that you can tighten it with. The length on my back was just a bit long but I would take longer over shorter any day of the week. The back protector also fit very well under my leathers and didn't cause any discomfort while riding on the track. It also provided excellent protection when I high sided at around 80mph.

Hope this helps,

Oct 8, 2012
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Blonderhanz: I'm 6'0" at around 195 with a waist around 36-37". I just got the large Sub 4. As far as fitting the length of my spine, it is perfect. But you are concerned about the waist strap. The strap is long, even for me, and I may have to someday have it shortened. With your smaller waist the large's waist strap will be way to big, try the medium, or modify the waist belt on the large. Sep 28, 2011
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freepers: I had a similar conundrum. I choose the large size as for my sub 4 back protector. I went the smaller direction due to similar circumstances for my previous back protector and in retrospect should have gone the larger size.

Get someone to take three or four measurements, then average them. This will give you the best fit.

Hope this helps.
Oct 29, 2012
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billyb39: Adam,

I'm not sure if you made the decision yet, but I wear 36" waist pants and I just purchased the large. They are a little loose for my taste, so I'd recommend you go with the medium. If I had both side by side to try on, I probably would have purchased the medium.

Aug 1, 2011
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MrDsylexia: I too was between sizes but as Anthony in the videos always says, "if you are between sizes, go for the next one up". The Large protector fits me perfectly. I am also 5'11/6' and 38 waist, it fits fine and has a lot of room to spare/ great adjustability. Nov 17, 2012
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MotoLeo: Adam, I am 5'9" with a 33" waist and wear a medium. The protector fits well and I have plenty of room to adjust. I would think that you would still fit in a medium. Aug 21, 2011
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MCMD: I'm between 6'1" and 6'2" with a 32" waist. I just bought the large and it's easy to get a good fit from the straps. Buy based on your height. Sep 5, 2011
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Pedro: I'm 5'11 and 1/2" Thin too. 32 pants. I got the large and it fits perfect. Straps fit snug. Go for the extra coverage. Oct 10, 2011
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WaldoT: Dear Adam,

Excellent choice! I am 6'6" and wear the large. Go with the medium instead.

Waldo T.
May 8, 2012
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Adam26: Thanks to all the respondants.
Sep 28, 2011
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Benjamin K asked: I currently use an older Technic/Knox full back protector, but it is 10 years old and of the one shot variety. I am very impressed with the specs on the L4 unit and the fact that taking a hit will not deplete from its ability to take another impact at the same point. However, it seems to be made out of a rubbery material and I am wondering how long it's good for until it starts decomposing? Is there a warranty? Feb 25, 2014
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Kenneth H: Hi! I do not know if any warranty? I have one and like it, not sure now how long I had it - I guess about 2 years or so. It is very good and seem to me will last many years! I live where it gets to around 45 C or 120 F in the summer! I have no problems with the sub4 and ware it when every I ride my bikes. both on and off the road.

Yes, expensive, but I believe will be happy with it over the short and long run - I am!
Oh! If tight jacket - will need to get a bigger size with the sub4.
Mr H
Mar 2, 2014
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Michael G: This is an excellent product , multi-impact , will save your bacon
hope you never have to us it , but if you do, you will be glad , get a chest protector too .. Be Safe
Feb 28, 2014
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Product Style RevZilla SKU ID Manufacturer Product # Availability
SM 617815 FPS-4-2-S In Stock: Ships next business day
MD 617816 FPS-4-2-M In Stock: Ships next business day
LG 617817 FPS-4-2-L In Stock: Ships next business day
XL 617818 FPS-4-2-XL In Stock: Ships next business day