Pickguard

A pickguard (also known as scratchplate) is a piece of plastic or other (often laminated) material that is placed on the body of a guitar, mandolin or similar plucked string instrument. The main purpose of the pickguard is to protect the guitar's finish from being scratched by the guitar pick.

As well as serving a practical purpose, the pickguard may also be used for decoration and is often made in a contrasting color to that of the guitar body (popular variants are white pickguards on darker guitars and black pickguards on lighter guitars). As well as plastic, other pickguard materials can include acrylic glass, glass, plywood, fabrics, metal, and mother-of-pearl/pearloid varieties. Expensive guitars may have luxury pickguards made from exotic woods, furs, skins, gems, precious metals, Mother of Pearl and abalone pearl.

The pickguard is a very common site for an autograph, since the signed pickguard can easily be detached and moved to another guitar or sold separately as a piece of memorabilia.

Pickguards come in various designs and shapes but designers usually try to match a and pickguard design. Both can be used to incorporate logos, branding and/or elements of the manufacturer's/customer's style.

Aggressive strumming with a pick can easily damage the polished surface of the guitar's soundboard. Pickguards fitted to acoustic guitars are usually made from thin (2 mm) sheets of plastic (such as PVC), attached with an adhesive just below the sound hole. The material should not be unduly thick or heavy since this might reduce vibration of the soundboard and alter the tone or volume of the instrument. Although not a job for the novice, a badly scratched pickguard could be removed and replaced by a guitar technician or luthier. On some older Martin guitars it is quite common to see the black pickguard curling up at the edges where the adhesive bond between the plastic and the wooden top has broken down. This does not usually present a problem and adds to the "character" of the instrument.

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Wikipedia