Mitutoyo Telescoping Gage Set Spring-loaded plunger expands within the bore (or groove), allowing determination of the internal diameter (or groove width). With knurled clamp. Supplied in a fitted case pouch. Range .5"- 6" Included in Set: .5" - .75" .75"-1.25" 1.25" - 2.125" 2.125" - 3.5" 3.5" - 6"