Air Plug Gauge 63 mm.

the gauging members of the plain plug gauges are made of suitable wear-resisting steel and the handles can be made of any suitable steel e.g. handles may be made of light metal alloys for heavy plain plug gauges, or suitable non-metallic handles may be provided for smaller plain plug gauges. The gauging surface of plain plug gauges are normally hardened to not less than 750 H.V. and suitably stabilised and ground and lapped. The plain plug gauges are normally of double ended type for sizes upto 63 mm and of single ended type for sizes above 63 mm.