Slide nut with female thread, washer and BIS RapidRail® spring. Ready-to-use pre-assembled for a quick fixing, and retains assembly in place before final tightening. Replaces tee-nut, washer and threaded rod with 1 piece assembly. No need to measure and cut rod! Material: metal parts made of steel 1.0332; spring(s) made of POM (polyoxymethylene), green. Zinc plated. Plenum rated - tested to ASTM E-84.