|OPTICAL FLATS PARALLEL SETS - PARALLEL TO .000004"|
|Type of Set||Size||EDP No.|
|Set Op-2AA, two parallels||1" x 1/2"||V839901|
|Set Op-2B, two parallels||1-1/4" x 1/2"||V839903|
|Set Op-2C, two parallels||1" x 1"||V839905|
Flats in optical parallel sets differ in thickness by approximately 0.0125”, providing a parallelism check at two spindle positions, each one-half turn apart. For metric micrometers, the difference is 0.25 mm.