This fitting is best described as an odd shaped "donut." It's purpose is to make self-reinforced branch outlets on a larger (one size or more) run of pipe. The base of the common weld-o-let has a saddle shape to fit the run pipe.
The outlet end of the weldolet has a beveled-end allowing for butt welding a pipe or fitting.
The Sockolet is also made much the same as the weldolet except that the outlet has a socket to match the socket welded piping fittings and pipe.
The socket outlet sizes are normally limited to the smaller (2" and under) pipe sizes.
The Thredolet is made much the same as the Weld-O-Let except that the outlet is threaded to match the normal tapered pipe threads.
The threaded outlet sizes are normally limited to the smaller (2" and under) pipe sizes.
A Latrolet is a weld on branch fitting that is attached to the run pipe at a 45° angle. The angle attachment is sometimes required on high pressure relief systems.
A Latrolet may be ordered with; a Butt-weld outlet end, a threaded outlet end or a socket weld end.
The Elbolet is made to be fitted on the back side of a long radius 90° elbow.
An Elbowlet may also be ordered with a Butt-weld outlet end, a threaded outlet end or a socket weld outlet end.