Features: Guitar neck shims are made of solid brass for enduring use to fit the guitar neck. Functions: These shims were used to change the angle of a guitar neck to give more adjustment space. Thickness Size: There are 0.2mm(4Pcs), 0.5mm(2Pcs) and 1mm(2Pcs) guitar shims for electric guitar bass player. Easy To Use: The brass neck shims are durable and portable to install. Suitable for most electric guitars and basses to protect musical from corrosion or damage. Specifications: Materials: Brass Size: about 5x1cm/1.97x0.39inch Package Includes: 4Pcs 0.2mm Guitar Neck Shims 2Pcs 0.5mm Guitar Neck Shims 2Pcs 1mm Guitar Neck Shims note: Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. Due to the difference between different monitors, the picture may not reflect the actual color of the item.