Has a weld bead inside, is NPT threaded at both ends, and resists rust and corrosion. For low-pressure plumbing applications including air, water, oil, natural gas, and steam. Certified for use in potable water applications. Threads conform to ANSI B1.20.1 standards. Material conforms to ASTM A-53 Type E, Grade A standards. Manufacturing conforms to ASTM A-733 standards.