The AXE GREEN LIT NOCKS FOR AX405 CROSSBOLTS are designed to fit .166 diameter crossbolts, making them a precise fit for your AX405 crossbow. These lighted nocks feature a super-bright LED system that is activated by the forward movement of the crossbow string, providing an audible click when properly secured. The metal injection molded construction ensures exceptional reliability and durability. With over 20 hours of lithium-powered battery life, you can enjoy extended burn time and easy identification long after the shot. Our fast shipping ensures that you'll receive your order quickly, so you can get back to hunting or target practice. The Lit lighted nock system is initiated by the forward movement of the crossbow string, engaging Nockturnal's patented crossbow string-activated linear switch with piston-driven assembly.Key Benefits and Features: Weight: 44 grains Diameter: .166 inches Battery Life: 20+ hours LED Type: Super-bright