... 1/4''-56'' carbon steel 20# ASTM A106 carbon steel cold forged teeType: Welding tee, Slip-on tee, Threaded tee, Socket Welding ... , BS10, BS4504, SAN1123, 1000/3, 1600/3, 2500/3, T/D, T/E, T/F, AS2129, etc. 4-Japanese (JIS) Standard: SS400, SF440 ... 1/2 (DN15) TO 80(DN2000;) ASTM A106 carbon steel cold forged tee