Trigger and switch assembly

An interchangeable switching system for an electrical device includes a trigger, first and second electrical contacts, and first and second interchangeable housings for mountably receiving the trigger and the contacts. The trigger has first and second camming surfaces and the first housing includes structure for mounting the first and second electrical contacts such that inward movement of the trigger causes the first contact to be forced by the first camming surface into electrical contact with the second contact. The second housing includes structure for mounting the first and second contacts in positions in which a predetermined inward movement of the trigger causes the first contact to be forced by the first camming surface into contact with a third electrical contact disposed in this housing between the first and second contacts. The third contact is positioned such that an additional predetermined travel of the trigger inwardly causes the third contact to be forced by the second camming surface out of engagement with the first contact and into engagement with the second electrical contact.