This joint connects two round tubes so that they can be bent at the connection point. Due to the toothing, the round tubes can be bent from the straight state in 27 ° steps and fixed with the hand screw. Up to max. 90 ° to each side. So 90 ° to the left or 90 ° to the right, so it can be bent by a total of 180 °. The legs on both sides are angled 0 °. For your understanding: The article TL257 has 45 ° angled legs at both ends.
An internal spring keeps the teeth apart when the hand screw is loosened so that they can move freely and the teeth are not in the way.
If we assume a pipe with a wall thickness of 2 mm, then round pipes with a Ø (outer diameter) of 20 mm = Ø (inner diameter) of 18 mm fit into the inner hole of the connection.
Or the plug of the connection fits into round tubes with a Ø (outer diameter) of 29 mm = Ø (inner diameter) of 27 mm.
With a Ø (average of 29 mm) round tube, you insert the end of the accessories into the hole of the round tube.
With a Ø (average of 20 mm) round tube, you put the round tube in the hole of the accessories.
These accessories are often used in the bimini, device holder, support stand, bathing ladder, sun roofs or reel construction for your boat.
When assembled, the joint is 66 mm long. It thus extends the pipe to 66 mm in length.