The Knox Micro-Lock Back Protector Upgrade Part 114 L2 is part of the latest Knox collection. MICRO-LOCK SOFT. SMART. STABLE. New Knox MICRO-LOCK back protector is the softest, most comfortable protector Knox has ever made and totally contour to the body. Knox MICRO-LOCK uses SMART technology and properties to keep the armour super soft to touch but it locks when impacted. The locking action increases the amount of impact absorbed by the protector and reduces the energy passed through to your body. Key Features / Points: CE Certified Breathable Soft & Flexible Tested at -20 / +40 Degrees C L: 45 cm W: 26.5 cm; Thick: 23 mm View all Knox Back Protector Insterts . View all Motorcycle Back Protection . PLEASE NOTE: The measurements above represent the actual size of the protector. The protector pockets should ideally be approx 1cm bigger all round. The protector opening should be at least 85% of the width of the protector.