These poly risers are used to extend microsprinklers above ground level so their spray can be above the plants.

The risers are a thick walled Poly tube which can have any 10/32 thread screwed into the ends. Most microsprinklers come with 10/32 threads for this reason.

Some risers come with 1/4" barbs already installed in one end ready to be attached to 1/2" poly tube or the end of a 1/4" microtube.