The 1/2 in. MPT 600 Series Compression Adapter connects to 1/2 in. FPT connection point on one end and 600 Series supply tubing or dripline (0.610 in. to 0.640 in. OD) on the other end. Tubing is inserted into the green compression ring, where an internal barb compresses the tube to hold it in place. This compression fitting is made of ABS plastic and treated with UV inhibitors to prevent fading and cracking.