Body: Aluminum, turned, with bright finish
Symbols laser engraved
Seal: Viton rubber
GN 742 fill/drain plugs are fitted with outside diameter d1 to fit screw holes with BSP threads included in DIN 3852.
The seal is retained in a groove undercut in the mating face,
which prevents it from dropping out and from extruding when
the plug is tightened. For this reason the seal can be of
a softer material which offers better sealing.
Maximum heat resistance: 180°C (356°F).