Aqua Ultraviolet® White or Black PVC Unions - Slip by Slip in various sizes
Aqua Ultraviolet® White or Black PVC Unions - Slip by Slip in various sizes
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These PVC Unions are made by Aqua Ultraviolet and have the same thread as any of their unions.   Great for quick and easy disconnection and re-installation. The gasketed seal between the two halves of the union make it a sensible way to connect and disconnect glued plumbing sections. And since shipping is free on all orders over $99 picking one up along with your pump or skimmer is practical.

A40116 - 2" Slip x 2" Slip Union in Black
A40032 - 2" Slip x 2" Slip Union in White
A40082 - 3" Slip x 3" Slip Union in White 

A40082, A40032, A40116