set2: 1 set x 6 high mechanics + 6 x Copper guitar pins Copper pins impossible to be broken, not only look beautiful, but also not easy to be oxidized Size: guitar pins: length 30mm, bayonet maximum diameter 5.3mm, pins puller: length 57mm, width 18mm Quality sealed mechanics Heavy Duty Internal Gear High tuners for steel strings (electric or acoustic) guitars (3L + ) Copper is harder , it can increased brightness and even added bass, This is because the hardness of the material transfers the vibration of to the top of the guitar with more efficiency. and the brass at the pin definitely increase the loudness and dynamics, it may actually increase the high frequency content of your guitar, let the tone more attractive. Color: Gold & Black-gold Material: metal/copper + ABS Size: 4 x 3.6cm Package Contents: 1 set x 6 high mechanics 6 x Copper guitar pins 1 x pins puller Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.