Plain Plug Gauge, Size - Go - 8.106mm to 8.110mm & Nogo - 8.290mm to 8.300 mm & Depth Go - 30.050mm to 30.105mm, Nogo - 30.437mm to 30.463mm, Go - Nogo Gauge (Required to check the Barrel plate Reaming Hole Long Barrel), Code - PPG8.1/30