Item Type: Guitar Tuning Peg ButtonsMaterial: Ebony + MetalColour: Black1Basic Specifications: The size of the mounting hole of this guitar knob is about (L x W) 3.8mm?4mm, which is easy to use 2Ebony+Metal: The guitar knob is made of high quality ebony+metal materials, which makes feel more comfortable to the touch, exquisite workmanship, good texture 3Scope of Application: This is a peg buckle handle that is widely applicable to the head button of electric guitars and folk classical guitars 4Long Service Life: The guitar knob is environmentally friendly, odorless, and durable, stable in performance, and long in service life 5Elegant Appearance: This is a peg buckle handle, with an elegant appearance, and is beautiful guitar head decoration6 x Guitar Tuner Button6 x Screw6 x White Washer6 x Black WasherOnly approximate size for tuner button mounting hole for reference, can not be totally exact. Only the approximate for reference. Customers can be be sure if this mounting hole is too big to install according to this size. But if the mounting hole is too small for you, would be hard to fit in. If so, please enlarge the hole with small file. So that this problem can be saved. Please check all very carefuly before order. Thanks for your cooperation.