The Legend Valve 3/4″ FNPT x 3/4” Sweat T-571NL No Lead Dielectric Union is a brass fitting designed for industrial plumbing applications. With a male thread size of 3 3/4 inches and a female thread size of 3 3/4 inches, this union allows for easy connection and disconnection of pipes. At 8 inches in height, length, and width, this dielectric union is a reliable and durable solution for various plumbing needs.