Size:0.5mm. 0mm, 2.0mm (three thicknesses). Guitar Nut Shims Brass Heightening Gasket: Made of brass, which is known for its sound transmission, hardness, and wear resistance. Enhance Guitar String Height: If you find that your guitar strings are consistently too low, especially during cold and dry seasons, using these gaskets allows you to effectively increase the height of the guitar nut.
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