PennEngineering® Screw Head, Spring-loaded - Metric PFS2-M4-72-BN-2

The PFS2 series consists of spring-loaded captive panel screws with external threads meeting ASME B1.1, 2A and ASME B1.13M, 6g standards, designed for tool or hand operation in sheet metals with hardness up to HRB 80 or HB 150. The screw and retainer are carbon steel with bright nickel over copper flash finish (CN); the spring is 300 series stainless steel and the retaining ring is nylon rated to 200°F (93°C). The PFS2-M4-72 variant has a 4.0 mm thread, 7.9 mm screw length, installs in a minimum 1.53 mm hole in sheet material up to 1.53 mm thick, and requires a minimum edge distance of 3.84 mm. The BN finish option, as specified in the part number, is black nitride per AMS2753, Section 3 for both screw and retainer. All variants remain captive during installation and removal.