Each parallel consists of two ground pieces which slide smoothly on each other and can be locked in position. They can easily be expanded to size in openings for quick reference measurements.
They can also be used in pairs as parallels. Range of this set is 3/8″ – 2 1/4″. Supplied in plastic wallet

Made of precision Ground tool steel. Easily expanded to size in openings for quick reference measurements. Lock desired size by set screws provided. Exact size can be set with micrometer. Furnished in fitted plastic case with size range markings. DIMENSION: 3/8~1/2″, 1/2~11/16″, 11/16~15/16″, 15/16~1-5/16″, 1-5/16~1-3/4″, 1-3/4~2-1/4″.

Features:
Complete with fitted case.
For layout, inspection, stop work, set-up, etc.
Made of high quality 45#steel, sturdy and durable.
6 Pair/Set Adjustable Precision Parallel Set, #EG02-5001
Length range from 1-3/4″to 5″ Closed. Thickness = 7 mm + – 0.2 mm
Quickly adjustable and locked with screws for micrometer measurement.
Size range: 3/8″ to 1/2″, 1/2″ to 11/16″ 11/16″ to 15/16″,15/16″ to 1-5/16″, 1-5/16″ to 1-3/4″, and 1-3/4″ to 2-1/4″