2.100 inches minimum and 2.160 inches maximum overall length, 1.380 inches minimum and 1.440 inches maximum overall width, 0.790 inches minimum and 0.900 inches maximum aperture diameter, one corner is chamfer .19 by 45 degrees. hole is not centered,is counterbore .890 in. min.,.900 in. max. and .250 deep special features, aluminum alloy 2024 material, qq-a-250/4,t3 fed spec single material response material document and classification

A flat metal or plastic item of various peripheral shapes having a solid (not laminated) cross-section. It is designed to maintain a predetermined distance between two surfaces. For round items without a hole having a solid rectangular cross-section use disk, solid, plain. For round or hexagonal items with only one hole centrally located and with the length (thickness) exceeding 25 percent of the outside diameter or distance across peripheral flats, see spacer, sleeve. The thickness between the two parallel bearing surfaces must be 0.006 inch, (0.152 mm) or more for items less than 1/4 inch (6.35 mm) across the peripheral diameter, or smallest overall outside dimension, or must be 0.016 inch (0.406 mm) or more for items 1/4 inch (6.35 mm) or greater across the peripheral diameter or smallest overall outside dimension. For items with a thickness less than those indicated above, see shim. For items with one hole centrally located conforming to the above dimensional criteria use washer, flat or spacer, ring as applicable. When thickness and/or outside_diameter_or_smallest_overall_outside_dimension_is_designated_as_a_tolerance/dimension_the_maximum_dimension_will_be_used_to_determine_compliance._excludes:gasket;_insulator_(as_modified)_and_mounting_pad,_electrical-electronic_component.____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________