Adapter, with Pg connection thread according to DIN 40430 and metric internal thread according to DIN EN 60423, with knurled collar. External thread: Pg 21 Internal thread: M 20 External thread length: 7 mm Internal thread length: 10 mm Outside Ø: 30 mm with connection thread sealing ring 987/...(please order separately!): IP68 Material: brass, nickel-plated