Westbrass 1-1/2" Zinc Bath Drain Body for 5/16" Stem, Polished Chrome, 793516SOCPZ-C Zinc construction Polished chrome finish blends into your existing fixtures Coarse-thread body 1-1/2 in. NPSM (1-7/8 in. by 11-1/2 UNC) exterior Use with a coarse-thread shoe and a tip-toe, twist-and-close, lift-and-turn or push/pull mechanism