Typically used on the engine control panel. Also used for the 19" X 8.5" master electrical panel (we believe for a short period of time starting in 1990).
Important notes: It is important to match the amp rating of the replacement breaker with the old breaker being replaced. Different ratings were used at different times depending upon what was being protected. If necessary, gain access to the back of the panel and check the rating on the side of the breaker before ordering.