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 94960 1/4" Composite-Style Coupler, 1/4" Female
Dynabrade 94993 1/4" Male Composite-Style Coupler with 1/4" Female Plug Assembly
Dynabrade 55034 3/8"-24 Female 5/8"-11 Male, 1-3/8" Length
Dynabrade 98263 3/8" NPT Male Plug
3M 27708, Cubitron II Roloc Durable Edge Disc 984F, 60+, YF-weight, TR, Maroon, 1-1/2 in, Die R150S, 7000045171, 200 per case
Insize 2435-E1608, BORE GAGES, measuring depth 120", range 4.0-6.3", 6940561979893
3M 67928, Cloth Belt 777F, P120 YF-weight, 3/4 in x 20-1/2 in, Fabri-lok, Single-flex, 7000120279, 200 per case 