An electric on-off switch which may optionally include a thermal trip including a bimetal strip.The switch comprises a housing having therein a stationary contact which is engageable by a movable contact carried by a contact spring. The spring is actuated by a mechanism including a tiltable operating lever which carries a release lever. An operating cam is provided on the release lever for depressing the contact spring and causing the movable contact to engage the stationary contact.When the switch includes a directly or indirectly heated bimetal strip, the release lever is pivotally carried by the operating lever which carries a torsion spring. The torsion spring biases the release lever into contact with a set screw secured to the bimetal strip and also urges the cam into contact with the contact spring. A pivotally mounted, elongate lever is preferably disposed between the set screw and the release lever. When the switch is tripped due to excess current the bimetal strip bows and displaces the cam from the contact spring and thereby allows the contacts to separate.The switch may be provided with a U-shaped mounting frame which can be oriented to one of two different positions. Also two or more switches may be ganged together and held together by a U-shaped bracket. A common rocker may be connected to the operating levers of the switches.