Log In / Register
0 Checkout
Firstgear Onyx Expandable Magnetic Tank Bag
  • Firstgear Onyx Expandable Magnetic Tank Bag
  • Firstgear Onyx Expandable Magnetic Tank Bag

Select qty:

Add to Wish List

Firstgear Onyx Expandable Magnetic Tank Bag


  • RoadTex 1000 denier nylon with PVC coating and UV protection
  • Non-slip material on bottom with heavy-duty magnets
  • Clear map pocket with hook-and-loop closure
  • Adjustable shoulder straps for use as backpack
  • Convenient soft-grip carrying handle
  • Soft flannel lining to protect valuables
  • Mounting base can be used separately as a map holder
  • Reflective piping and logo
  • Reinforced sidewall
  • Zippered mesh pocket inside of the lid plus elastic penholders
  • Detachable key holder on inside
  • Rain cover and adjustable shoulder strap included
  • Additional safety bungee cord provided
  • Compressed: 14"L x 10"W x 8"H / 1,120 Cubic Inces
  • Expanded: 14"L x 10"W x 11"H / 1540 Cubic Inches
Product Style RevZilla Item # Manufacturer Product # Availability
Firstgear Onyx Expandable Magnetic Tank Bag 527738 107247 In Stock: Ships within 24 hours


Orders $39.99 and over qualify for our fast free shipping offer. Click Here for FREE Shipping Terms and Conditions.

Please see our International Orders page for orders shipping outside the US.

We show real-time availability on this product page when you select the size/color item you want.  Most items will ship the same business day an order is placed,however if an item requires additional processing time a message will be shown indicating such.

See our full Shipping Policy for further details.


If your order arrives and it is not right, we will we'll fix it, NO NONSENSE, we promise.

Doesn't fit or just not happy with it? You can return any new, unused and unaltered item within 30 business days of delivery receipt of your item. We will issue a full refund to your original payment method.

See our full Return Policy for all of the pertinent details.

Write a Product Review for a chance to win our monthly $100 giveaways.
Firstgear Onyx Expandable Magnetic Tank Bag 4.9 5 10 10
Heavy but great To get it out of the way: this thing is a beast. Heavier than I expected, but I've only used tank bags with straps before, so I'm maybe not the best judge. But I was surprised when I first picked it up. The weight is something of a good thing though: the magnets are huge, so it isn't going anywhere. I have no qualms about high speed riding in winds, nor about riding with the tank bag heavily loaded down. Zippers are tough, carrying straps are good, and the wings with the magnets fold up and stick together nicely so you can walk around a store without looking like you're carrying a small stingray. The two outside pockets pretty nicely fit the carrying strap and the rain cover, so the bag can be completely empty otherwise. The only other downside (or me being obtuse) is the strap thingy at the bottom: a clip to (I think) attach to a loop you could run around your frame at the back of the tank. I haven't done that (perhaps I should), since I don't want extra straps flapping around when I'm not riding with the bag, and the magnets are enough...so I've sort of tucked the strap up into the zip off base (also a nice feature). Not ideal, but it works: just a bit finnicky at first. All round a good deal for the price, and is serving me well for commuting and long trips. June 14, 2016
very large well made tank bag It holds a lot of stuff. It's well made like a nice piece of luggage. Easy on, easy off. Easy carry handle and backpack straps I've not had to use so far. February 16, 2016
Awesome bag with plenty of space. Easily fits my 12.2" tablet. Very sturdy construction. The magnets are strong enough to hold it on the side of my toolbox at work. Its a bit to large to ride on the tank of my sportster but the flaps clip together and it slides down over the sissy bar nicely. With the included bungee cords it's very secure. Only thing i would change is the sunglasses pouch. There is no protection from the zipper scratching up your lenses. August 4, 2015
just what I needed works well not too big or small. A little heavy to carry around with me but that's ok September 2, 2013
Nice big bag with a fairly small footfrint This bag is great. Just rode with it from Tennessee to Maine and back. Didn't expand it until halfway on the trip and it was great to have the room for gloves, rain pants, etc. The map holder works fine if you unzip the lid first. Otherwise, it's hard to get a map in or out past the glasses compartment. September 29, 2012
More than enough room I was looking for a bag that would be big enough to take my normal riding 'must haves' as well as have room for the little things that come along on different rides. Keep in mind, this is a fairly big bag, even more so when expanded. Bag fits everything that I need no problem, sits nice on the bike and stays where the magnets are placed. Tabs on the zippers are nice and big and easy to access even with riding gloves on. Its nice to have the bottom unzip off, providing back pack straps if you need to carry it any distance. Only complaint I have is that it doesn't appear to be 100% waterproof but they have provided a water proof cover that can be put on easily. I have folded it up small enough to fit it in the sunglass case. I haven't hit any hard downpours yet, but it has held up with light drizzle just fine without the waterproof cover on. July 16, 2012
great tank bag! I was looking for a small tank bag, this is not what I consider small but I liked the fact that it didn't have side storage compartment. This bag is very roomy and for a daily commuter like myself, it's just perfect. It also fit well on my 04 gsx-r 750 tank. The description of this item is spot on. April 23, 2012
Great Bag...tough on maps I recently used this bag on a trip to Big Bend NP and it worked great helping me store a lot more gear. It carried my SLR camera and 32oz water bottle with other misc. items with ease in the non-expandle position. My only complaint is the sunglasses case gets in the way of installing my maps and makes it a little difficult. I think if the zipper for the map case was on the side instead of the aft position, it would be much easier and possibly prevent tearing of maps. Overall though, great bag and looked good as well on my black FJR. April 11, 2012
2 next>>
Use our Product Q&A for a chance to win our monthly $100 giveaways.

Have a functionality, fit, or otherwise product-specific question about the Firstgear Onyx Expandable Magnetic Tank Bag? Ask it here! If you have a customer service or shipping question, please direct it to our Customer Service department.