This machined steel reamer is made specifically for enlarging a guitar endpin hole to accept a 15/32" or 1/2"-diameter endpin jack. It won't chip the finish, and it's semi-fluted to help keep the hole round.
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Bridge Pin Hole Reamer
Our special wooden-handled steel reamers are designed to properly taper the holes for bridge pins. We offer two reamer sizes for accurate holes and better fit.