Section R. 408.12304 - Definitions; CRule 2304.
(1) "Concurrent" means acting in conjunction, not necessarily simultaneously, and is used to describe a situation wherein 2 or more controls exist in an operated condition at the same time.(2) "Counterbalance" means a mechanism used to balance or support the weight of the slide and upper dies.Mich. Admin. Code R. 408.12304