Screw Pitch Gage, Inch 51 Leaves, Starrett

Starrett screw pitch gages are among the most useful tools in any mechanic's toolbox. They quickly determine the pitch of various threads. These gages consist of a substantial steel case with a number of folding leaves at both ends, each leaf having teeth corresponding to a definite pitch, marked on each leaf. The screw pitch gage features a locking device at both ends of the case, so leaves can be securely locked in position for use. Leaves have a special narrow design, permitting checking internal threads in nuts, etc., as well as external threads.
Measures 60° threads from 4 threads per inch to 84 threads per inch
Leave Sizes: 4, 4.5, 5, 5.5, 6, 7, 8, 9, 10, 11, 11.5, 12, 13, 14, 15, 16, 18 threads per inch (TPI)
Leave Sizes: 20, 22, 24, 26, 27, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50 threads per inch (TPI)
Leave Sizes: 52, 43, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 78, 80, 82, 84 threads per inch (TPI)
Starrett catalog number 472