Alnicov Guitar Bass Pocketable Stainless Steel Tool Multi Spanner Wrench for Guitar Switch Knob Tuner Guitar Accessories. 1 x Spanner. One end of the multi-function wrench is toothed to loosen the nut; the other end is tightened,it can be used for many different sizes of nuts, very suitable for your guitar case;no need to carry multiple wrenches.
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