I think the prize goes to Zevon8 this time.
It is a mains power connector as used on Royal Navy ships and submarines.
The thing does lock into place and is sealed by an O-ring to make a waterproof connection. For those who are into such things it would probably be rated IP66.
If I remember correctly, the switch on the socket locks the plug into place when the power is turned on.
The stainless steel tab on the right hand side of the picture is for pulling the plug out of the socket.
JimB
It is a mains power connector as used on Royal Navy ships and submarines.
The thing does lock into place and is sealed by an O-ring to make a waterproof connection. For those who are into such things it would probably be rated IP66.
If I remember correctly, the switch on the socket locks the plug into place when the power is turned on.
The stainless steel tab on the right hand side of the picture is for pulling the plug out of the socket.
JimB