... 1.Grade: J55, K55, N80, L80,P110 2.Thread: BTC,STC,LTC 3.Standard: API 4.Place of Origin: China 13 ... coupling from 4-1/2” to 13-3/8”TYPE: NUE, EUE (tubing coupling), STC, LC, BTC (casing coupling).SURFACE TREATMENT: Whole ... 88*269.8823.1610-3/4”STC298.45*203.2020.7810-3/4”BTC298.45*269.8825.7411-3/4”STC323.85*203 ... .2022.6411-3/4”BTC323.85*269 ...