Gold Tip Nock Collar .166 Series 600 Fits Pierce 600 1dz. May be used with GTO nocks or pin bushings. Machined rings correspond with specific spine of arrow. (4 rings = 400) Specifications for Gold Tip Nock Collar: Manufacturer: Gold Tip Inner Diameter: 0.166 in Quantity: 12 Features of Gold Tip Nock Collar Spine specific fit 6 spine - 2.5 gr. Package Contents: Gold Tip Nock Collar Protective nock collar desgined to fit over the nock end of Pierce Tour Pierce Platinum and Pierce arrows. May be used with GTO nocks or pin bushings. Machined rings correspond with specific spine of arrow. (4 rings = 400) Features/Specifications: Spine specific fit6 spine - 2.5 gr.