US STANDARD THREADS - Detailed instructions ensure worry-installation. the thread specification of inlet is 1/2"-14 NPT,suitable for standard shower pipes. The thread specification of outlet is 1/2"-14 NPT (compatible with 1/2" IPS thread),suitable for sprinkles of standard interface. THICKENED SHOWER ARM - The pipe is made of marine-grade 304 stainless steel with over twice strength of ordinary brass,good resistance to acid,alkali and salt,long-term corrosion resistance to avoid shower heads blockage due to rust residues,especially suitable for hard water and hot spring water. UNIVERSAL REPLACEMENT SHOWER ARM - Suitable for bathroom shower system,rain shower head,hand held shower head combo. EASY TO INSTALL - Includes a 2.5" flange that covers unsightly old holes,and comes with teflon tape to prevent leaks. Easy to install without plumbing experience. MORE CHOICES - Various colors and sizes shower pipe arm for you to choose,providing you with a more comfortable bathing experience..