7mm, it will make your diy work smooth.35mm, 9.5mm and 12. This kit includes drum sanding bit and band mandrel 6. This is a set of 102 pieces drum sanding kit. Length of shank: 38mm. 2 x 102PCS of 80Grit Drum Sanding Kit with Band Mandrel 6.35/9.5/12.7mm for Rotary Tool Nail Drill Bits Abrasive Tools Accessories.
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