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The only way to get true, accurate line spacing when checkering backstraps, triggerguards, grip frames, ribs and hammer spurs; anywhere an improved gripping surface is needed. Finer cuts give a nice matting effect to reduce glare and light distortion. Procedure is very similar to wood checkering. Layout your master lines (or use a guide like our .45 Checkering Guide), then establish the pattern by moving the file a few teeth each time using the previous lines as the guide. Once the pattern is fully laid out, bring to final depth with a 60° needle file.