PennEngineering® Large Knob, Spring-loaded - Types PF11MF and PF12MF - Unified PF12MF-440-1

PF12MF-440-1 is a spring-loaded, flare-mounted captive panel screw with a large knob, designed for secure fastening and easy access in thin panel applications. It features a #4-40 thread (ASME B1.1, 2A), a hardened carbon steel screw, aluminum knob and retainer, and a 300 series stainless steel spring. The part has a natural finish on the knob and retainer, with a zinc-plated screw per ASTM B633, SC1 (5µm), and a minimum float of 0.25 mm in all directions. It installs into sheets as thin as 0.041 inch with a maximum hole size of 0.187 inch and a total installed height of 0.450 inch, using a #1 Phillips driver.