The AP12-1-72F-103 is a two-pole, fully sealed magnetic circuit protector designed for reliable overcurrent protection in demanding environments. It features a series trip configuration with a nominal current rating of 10.0 amperes and is compatible with DC, 50/60Hz, and 400Hz circuits. This model incorporates a long time delay with a 135% trip point and an added inertial delay ('F') for enhanced inrush pulse tolerance. As a hydraulic-magnetic protector, its trip point remains stable over a wide temperature range, and its 'trip free' action ensures the circuit opens during an overload even if the handle is held on. Common applications include communication equipment, navigation systems, aircraft instrumentation, and power supplies.