20-Amp Zinsco R38-20 circuit breaker with red toggles. Zinsco was the original EOM manufacturer of this brand. Older breakers were also known as a Magnatrip Breaker. These are obsolete and are ony available in recondition. In the 1950's this was a very popluar brand. They appear all over the USA in older homes, such as This Old House. In later years Sylvania purchased the brand, then later it was Challenger, then still it was Thomas&Betts. Today only a knock-off brand is made by Unique Breakers. Nick names like Magnatrip, QB, QFP, QFB where also part of the Zinsco group. In many cases the bus bar is damaged from overloading. We stock repair kits for some panels, so please call Breaker Outlet for details at 800-321-8998.