NAP Thunderglo Lighted Crossbow Nocks Green Universal Fit 3 pk. Polycarbonate blend Nock with aluminum shaft;Bright LED Illumination;Auto ON when nock is shot;LED Stays ON until user unclicks the nock;Universal collars fit most crossbow boltstable.productattributes, .productattributes td { border-bottom: 1px solid #ddd; border-collapse: collapse; padding: 2px; text-align: left; } Item Category Code: 3400 Product Group Code: 3400F Product Sub Group 1: 3400F1 Product Sub Group 2: 3400F1B Pack Size: 3 Inactive: No