That's the plug I was thinking about, too. Those wicked-looking things were available in 50 amp (full plug) and 25 amp ("half plug") sizes. They were also used in both A.C. and D.C. (carbon arc) circuits. What was so insidious about these things was that they were completely interchangeable
. I ran into a few of these stage plugs when I was with the I.A.T.S.E. many years ago. At that time, touring companies still used old "piano boards" that were equipped with porcelain receptacles, old resistance dimmers and the usual knife switches and fuses. There were also "plugging boxes" available for connecting anywhere from 2 to 6 stage plugs to one dimmer circuit. Those things would spark like July fourth fireworks when you hot-plug them
. It was common practice to wear asbestos gloves when handling these things because of the relatively small "safe" handle area, and the heat produced in these connectors.
[This message has been edited by mamills (edited 01-05-2006).]