AP17-1-65-252 is a fully sealed hydraulic magnetic circuit protector from the Airpax AP series, designed for accurate and reliable circuit protection with inverse time delay and trip-free features. This single-pole series configuration unit operates at 50/60Hz with an extra-long time delay (delay code 65) and a nominal current rating of 2.5 amperes. The protector maintains consistent trip current over a wide temperature span, unlike thermal circuit protectors. It features an auxiliary switch rated at 3.0 amps at 120 VAC or 50 VDC, and weighs approximately 1.8 ounces (49 grams) per pole. Common applications include power switching and circuit protection in environments requiring stable performance across varying temperatures.