Fit for Martin or any brand acoustic guitar Offer you a more attractive tone than other cheap plastic pins 100% brand new, high quality Material: brass Length: 29.5mm Width: 8mm the biggest install diameter:52mm Package include: 6 x guitar pins Note:Light shooting 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 +/- 1-3 cm.