I list the size of blank tubing coupling for manufacturing finished coupling for your reference, if you interested, pls let us know, we will give a good price.

Size of Blank....

API Tubing Pup Joints - Manufactured according to API Spec 5CT using prime API monogrammed, seamless oil country tubing. Optional diameters, lengths, weights, and grades are....

API Tubing coupling:
Size range from 2-3/ 8" to 4-1/ 2"
EUE or NUE
Steel grade including J55/ K55, N80, L80, P110
API Casing coupling:
Size rang from 4-1/ 2" to 13-3/ 8"
....

Coupling stock: ( Other size is avaliable)
2 3/ 8â € � OD 79x WT 11mm
2 7/ 8â € � OD 94.5x WT 12.6mm
3 1/ 2â € � OD 115x WT 14.2mm
4 1/ 2â € � OD 128x WT 14mm
5 1/ 2â € � OD 154.5x WT....

API 5CT Tubing,
Range from: 2 3/ 8â € � to 4 1/ 2â € �
Length: R1, R2
Type: NUE or EUE
Grades - J-55, N-80, N-80, L-80, P-110

API Tubing Blank Pup Joints - Manufactured according to API Spec 5CT using prime API monogrammed, seamless oil country tubing. Optional diameters, lengths, weights, and grades are....

API 5CT Casing pipe,

Range from: 4 1/ 2â € � to 13 3/ 8â € �
Length: R1, R2, R3

End Type: Plain, LTC, STC, BTC

Steel grade including J55/ K55, N80, L80, P110