This is a Supply Giant Adapter fitting made of copper. In particular, the Adapter has on one end a 1/2 inch female solder cup and on the other end a 3/4 inch connect with female thread, both nominal diameters. The fitting is designed to adapt pipe with a male threaded end to copper pipe with an outer diameter of 5/8 inch. Furthermore, the part is produced to meet all applicable standards. ⚠ California Proposition 65 Warning: This product is known to the state of California to cause cancer, or other reproductive harm. For more information, go to www.p65warnings.ca.gov.