Ring and Plug gauges

API thread Gauges usage:

1.Used for checking API internal & external thread.
Conform to: API 5B

and 7. CSG,LCSG,LP,BCSG,TBG,UPTBG

2. Used for checking API internal and external threads.

Spec 5B:

CSG 4-1/2 to 20"

LCSG 4-1/2 to 20"

LP 1/8 to 12"

BCSG 4-1/2 to 6"

TBG1.050 to 4-1/2"

UPTBG 1.050 to 4-1/2"

3.Spec 7-2

NC10 to NC77

REG 2-3/8 to 8-5/8"

FH 3-1/2 to 6-5/8"

IF 2-3/8 to 5-1/2"