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

Dynabrade 95544 Gear Grease, 2.5oz. Tube
Dynabrade 40610 Electric Dynafile II Abrasive Belt Tool
3M 19076, Cloth Belt 577F, 80 YF-weight, 3/4 in x 18 in, Fabri-lok, Full-flex, 7000119452, 200 per case 
