Feature: 1.Every product has a unique Manufacturing Part Number label on the inner package that proves it has been qualified,which include Part Number,Model Number and inspection date information;2.If you have any questions about the item,please provide us the Manufacturing Part Number for checking,your 3.Used for shining decoration andRetain the string as well4.Easy to install,convenient to use 5.Reduce string friction to save the strings,more accurate tuning 6.Package includes 50 sets of string retainer parts,each set includes 2pcs guitar string retainer ,2pcs screws and 2pcs spacersSpecificationColor:GoldScrew Length:11mm, 13mmString Retainer:Approx.12 x 6mm/0.47 x 0.24inch(L x W)Weight:150gPackage Includes: 100 x guitar string retainer 100 x spacers 100 x screws