DIG's PVC coupling is used to connect 1/2 in. (.700 O.D.) poly tubing to 1/2 in. PVC pipe. The slip side the coupling is glued onto the end of 1/2 in. PVC pipe with PVC glue. Then the poly tubing is connected to the compression side of the coupling by holding the PVC coupling in one hand and the drip tubing in the other, and forcing the drip tubing into the fitting compression side for about 1/2 to 3/4 in. by walking or wiggling the drip tubing back and forth into the fitting. This adapter is primarily used to connect 1/2 in. poly tubing to existing or new PVC sprinkler pipe. Color: Black.