The guitar spanner tuner wrench is quality stainless steel , owns and long service life. Soft backing keeps the metal off your gear. Handy pocket‑size wrench quickly fixes loose , pots, switches and tuner. end of the multi spanner is toothed for loosening a nut; the other end tightens it. Easy to use. This pocket‑sized tooth‑shaped wrench will tighten or loosen most on the guitar, such as output , control potentiometers, pickup switches, tunings pegs, . All edges and surfaces are chamfered and polished to avoid damage to the area around the instrument. And specially angled for clearance over a guitar body or peghead. Installing a new guitar is very easy, you can adjust the tension so that your guitar sound is stable. For use on many different sizes of , which makes it great for your guitar box.