The Knox CE 1 Elbow Armor fits all Men's Roland Sands Design Jackets for premium elbow impact protection. Knox's Micro-Lock Armor has been designed to be super soft, highly protective, and, MOST importantly, STABLE across all climates and environments. This temperature stable armor holds its shape and protective properties whether you're riding across the barren desert of Death Valley or in the frozen wilds of Alaska. Knox has have tested all types of super soft armor, and they are all sensitive to temperature changes and have also found that this affects the performance and lifespan of the protectors. Using SMART technology and properties which keep the armor super soft to touch, but it locks when impacted, Micro-Lock Armor increases the amount of impact absorbed by the protector, reducing the energy passed through to your precious limbs.