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Alpinestars Nucleon KR-3 Back Protector

Item: P387528

Top-of-the-line trackday back protection from Alpinestars. The Nucleon KR-3 packs back and kidney armor along with rib protection into one package. Read More

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Product Details

Alpinestars Nucleon KR-3 Back Protector

Highly flexible and breathable, the Alpinestars Nucleon KR-3 Back Protector is engineered for maximum performance. Using hard shell backed with a soft viscoelastic PU foam compound, the KR3 achieves both max comfort and extraordinary impact absorption. 


  • 3 waist-to-shoulder dimensions in order to cover all body sizes
  • Lattice-structured back shell plate constructed from a high performance polymeric material blend for optimized flexibility and excellent weight-saving properties
  • Soft viscoelastic PU foam compound
  • Ergonomic design design to absorb high impacts and allow maximum breathability and air flow
  • Nucleon PU foam on the central spine for extraordinary impact absorption performance
  • Convex central hard shell provides highest protection for the spine
  • Horizontal flex grooves for adaptive fit in all riding positions
  • Adjustable rib protector constructed of high performance polymeric material blend for additional side protection
  • Shoulder blade protective padding extensions protect the acromion bone
  • Waist adjustment for customized fit
  • Slim vented kidney belt for added position stability and security
  • Adjustable, detachable elastic shoulder straps
  • Compatible with the Alpinestars Nucleon KR-C Chest Protectors (sold separately)
  • Compatible with the Alpinestars Nucleon KR-TB Protector (sold separately)
  • CE certified to EN 1621-2:2014 Level 2
Product Style RevZilla Item # MFR. Product # Availability
Product Style Black/Red / XS RevZilla Item #1242702 MFR. Product #6504718-13-XS AvailabilityIn Stock: Ships next business day
Product Style Black/Red / SM RevZilla Item #1242703 MFR. Product #6504718-13-S AvailabilityIn Stock: Ships next business day
Product Style Black/Red / MD RevZilla Item #1242704 MFR. Product #6504718-13-M AvailabilityIn Stock: Ships next business day
Product Style Black/Red / LG RevZilla Item #1242705 MFR. Product #6504718-13-L AvailabilityAvailable: Requires 1-3 business days of lead time prior to shipment
Product Style Black/Red / XL RevZilla Item #1242706 MFR. Product #6504718-13-XL AvailabilityAvailable: Requires 1-3 business days of lead time prior to shipment


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

Product Description
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Reviews & Questions

5.0 / 5.0
1 Review
5 Stars
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Bang For The Buck
5.0 / 5
Protection & Durability
5.0 / 5
5.0 / 5
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Air Flow
4.0 / 5
Bang For The Buck
5 / 5
Protection & Durability
5 / 5
5 / 5
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5 / 5
Air Flow
4 / 5
I have been using this in the summer heat and humidity,theres almost no difference in air flow.This baby molds to you in a few minutes and literally disappears under the jacket or suit.I added the kr/c chest protector harness so i'm able to use this with any jacket I own.Buy it,you wont be disappointed
July 13, 2018
Start typing your question and we'll check if it was already asked and answered. Learn More
Browse 2 questions Browse 2 questions and 1 answer
Does this work with a neck brace?
A shopper on Nov 19, 2017
Can you attach a chest protector to this back protector?
Alec G on Sep 29, 2017
BEST ANSWER: alpinestars chest protector fits on the shoulder straps
1 Customer Reviews
1 5/5
2 Questions & 1 Answers
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