J.W. Winco, Inc., a supplier of standard industrial machine components now offers GN 252.5 Stainless Steel Threaded Plugs in metric sizes.
These RoHS-compliant threaded plugs can be used as spring retention units or as plugs to keep debris from entering into critical threaded areas. The PRB thread coating (polyamide allround coating) acts as a clamping lock, preventing the locking screw from inadvertently being loosened and becoming detached.
Plugs are made of stainless steel, American Standard Series 303 (European Standard No. 1.4305). They are available with or without thread coating (polyamide overall thread coating). Thread sizes range from M12 to M27.