Adjustable parallel pairs are individual pairs of matching-sized parallels used to keep items level for machining or inspection. 

Solid, with set screws, each marked from the manufacturer.

Set of 4 parallels included sizes:

• 1/2 in to 11/16 in
• 11/16 in to 15/16 in
• 15/16 in to 1-5/16 in
• 3/8 in to 1/2 in