PennEngineering® Large Knob, Spring-loaded - Types PF11MF and PF12MF - Unified PF12MF-832-2-2

The PF12MF series consists of large knob, spring-loaded, flare-mounted captive panel screws with external threads compliant to ASME B1.1 and ASME B1.13M. The assembly includes an aluminum knob and retainer, a hardened carbon steel screw, and a 300 series stainless steel spring. The screw features a knurled cap, zinc-plated finish per ASTM B633, and installs into a minimum panel thickness of 0.084 inches with a maximum screw thread length of 0.350 inches. The part allows for a minimum float of 0.010 inch in all directions and has a 0.024 inch shoulder, ensuring positive stop during installation. The standard driver recess is #2 Phillips. The PF12MF-832-2 variant, corresponding to a #8-32 thread size, includes a 0.072 inch minor thread diameter and a 0.060 inch thread depth, mating with a 0.266 inch maximum hole size in the panel.