... .Casing Length: R1,R2, R3 API 5CT Casing 1.Casing Sizes: OD 4-1/2"~20" 2.Casing Grade: H40, J55, ... 5CT Casing, Tubing, Coupling. Our factory manufacture Casing, Tubing: According to API SPEC 5CT Casing . Casing Steel grade: J55, K55, L80 ... . Range Tubing: From 2-3/8"to 4-1/2"(EUE/NU) Casing: From 4-1/2" to 20", Casing Threads: BTC, LTC, STC ... P11012.415315.3412.19J55,K55,N80,L80,P110 API 4 1/2"Oil casing