• First, their purposes are different. Funny Pipe is used as a flexible connection between the lateral line and the sprinkler.
1/2" Poly Pipe is most commonly used as a lateral line in the drip (micro irrigation) portion of a sprinkler system.
• Second, the ID (inner diameter) size is different--Funny Pipe is roughly 3/8". 1/2" Poly Pipe's ID is a little over 1/2". Poly pipe fittings and Funny pipe fittings cannot be used interchangeably.
The following pictures show some examples of Poly Pipe and Funny Pipe (Swing Pipe) fittings.