PEM^®self-locking fasteners (Type LK/LKS/LKA) permanently retain their inherent flexing action, permitting

repeated use and effective prevailing locking torque.

The unique PEMFLEX^® self-locking feature with EF or MD finishes, meet the locking torque requirements for 250°F nuts of NASM25027 specification. The self-clinching feature is the same tried and proven design preferred and appreciated for fast, simple assembly. These fasteners do not protrude through the reverse side of the sheet and provide positive, permanent attachment with high torque-out (many times greater than locking torque) and pushout resistances.

PEM all-metal, self-locking fasteners are available in steel, stainless steel, and aluminum. Types LK (steel) and LKS (stainless) are treated with a black dry film lubricant for better locking performance. Type LKA (aluminum) must be used with a lubricated screw. The PEM design utilizes two rugged, semicircular flexing jaws instead of several less-supported segments. The greater ruggedness and retention of this PEMFLEX action prevents relaxation and loosening of the fastener in severe service.