This is a Supply Giant c x c x c tee with a cast brass construction. In particular, all the solder cups of the fitting have a diameter of 4 inch nominal size, for use with copper pipes with an outer diameter 4-1/8 inch. Furthermore, the fitting 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.