The ultra-lightweight Nucleon KR-1 CELL Back Protector insert is developed in three waist-to-shoulder dimensions to cover all body sizes. Unique cell micro-structure designed for advanced energy absorption, adaptivity, maximum breathability and air flow.; Cell Technology back protector is constructed from a high performance polymeric material blend for optimized flexibility and excellent weight saving properties Extended lower back protector offers more protection to the rider Highly perforated for maximum 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 protector by removing the adjustable straps Compatible with the Nucleon KR-TB 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