Weldtron UI and Weldtron UI-1 idle control modules.

Upgrade or modify any machine to idle automatically.
No external sensors required.  Totally self-contained with current sensors.

Have a good working R-57 Vacuum idler control but don't want to change the whole system over to a new complete electrical system.  You're in luck.  The Weldtron-UI can now be used to upgrade existing R-57 vacuum idler controls without the need to replace ANY electrical or mechanical parts.
An inexpensive way to modernize that old idler.