Abstract: A connector unit for connection of a fluid line to the mattress of a waterbed. The unit comprises a first connecting piece assigned to the waterbed mattress, a second connecting piece assigned to the fluid line and a connecting sleeve which while in mounted position encompasses the first connecting piece and the second connecting piece in part at least. At least one of the connecting pieces has a thread and is provided as a screw type socket. The connecting sleeve is provided with a thread for threaded engagement with said at least one screw type socket. The connecting piece without thread is of clamping type and provided with a collar which protrudes radially outward.