Thread
nominal size
Outer diameter
[mm (in)]
Threads per inch
(TPI)
Pitch
[in (mm)]
Inner diameter
[mm (in)]
Cable diameter
[mm (in)]
PG7 12.5 (0.492) 20 0.05 (1.270) 11.28 (0.444) 3 to 6.5 (0.118 to 0.256)
PG9 15.5 (0.610) 18 0.05556 (1.4112) 13.86 (0.546) 4 to 8 (0.157 to 0.315)
PG11 18.6 (0.732) 18 0.05556 (1.4112) 17.26 (0.680) 5 to 10 (0.197 to 0.394)
PG13.5 20.4 (0.803) 18 0.05556 (1.4112) 19.06 (0.750) 6 to 12 (0.236 to 0.472)
PG16 22.5 (0.886) 18 0.05556 (1.4112) 21.16 (0.833) 10 to 14 (0.394 to 0.551)
PG21 28.3 (1.114) 16 0.0625 (1.5875) 26.78 (1.054) 13 to 18 (0.512 to 0.709)
PG29 37.0 (1.457) 16 0.0625 (1.5875) 35.48 (1.397) 18 to 25 (0.709 to 0.984)
PG36 47.0 (1.850) 16 0.0625 (1.5875) 45.48 (1.791)  
PG42 54.0 (2.126) 16 0.0625 (1.5875) 52.48 (2.066)  
PG48 59.3 (2.335) 16 0.0625 (1.5875) 57.78 (2.275)