The shank is electrically conducted to the metal workpiece through the chuck and table,
the LED lights up and the beeper sounds(only for 6566-3E),
when the ball touches the workpiece
Not suitable for rotary use. Hardened shank and contact ball
Hardened shank and contact ball

3M 27259, Ultra Durable 5 inch Power Sanding Discs, Universal Hole, 120 grit, 7100188461, 5 per pack
3M 04258, Scotch Printable Flatback Paper Tape 256, White, 2 in x 60 yd, 6.7 mil,24/Case, 7000123288
Dynabrade 95843 Dynabrade Air Lube 10W/NR, 1 Gallon 