Alpinestars Nucleon KR1 Cell Back ProtectorThe Alpinestars Nucleon KR1 Cell Back Protector uses Cell Technology for a lightweight back protector with plenty of flexibility. Add the KR1 underneath your race suit or whatever gear you're running for a full coverage back protector that straps to your body.Features: Cell Technology back protector is constructed from a high performance polymeric material blend for optimized flexibility and excellent weight saving properties Developed in three waist-to-shoulder dimensions in order to cover all body sizes Extended lower back protector offers more protection to the rider Highly perforated for maximum breathability and ventilation Horizontal flexion grooves for an adaptive fit in different riding positions Adjustable and detachable elastic shoulder straps via a snap fit system for greater comfort Compatible with the Nucleon KR-C chest protector by removing the adjustable straps Compatible with the Nucleon KR-TB tail bone protector for extended lower spine protection Height adjustable kidney belt featuring dual hook and loop closure system for easy, secure closure Soft Bio-Foam padded chassis for maximum comfort CE certified to EN 1621-2:2014 Level 2