Serving our customers with quality and safety first.
5.0in.
0.750in. ⁓3/4"
provided
glass, borosilicate crown
A flat, transparent piece of glass, generally of fused quartz, with one or both principal surfaces polished to within a few millionths of an inch of a true plane. It is used in conjunction with a monochromatic light source to measure the flatness of precision finished surfaces, and to determine the distance and parallelism between precision finished surfaces by comparison with known standards. In operation the flat is superimposed, reference surface downward, on the parts under test and when illuminated by monochromatic light the rays reflected from the reference surface are either reinforced or neutralized by the rays reflected from the surface under test producing interference bands which reveal any variations in the thickness of the film of air between surface under test and the flat. Excludes optical parallels.
Indicates there is no data in the hmirs and the nsn is in a fsc not generally suspected of containing hazardous materials.
Item does not contain precious metal.
No known electrostatic discharge (esd) or electromagnetic interference (emi) sensitivity.
Represents items with no adp components
The item does not have a nuclear hardened feature or any other critical feature such as tolerance, fit restriction or application.
HMIC: Hazardous Material Indicator Code. A one position code that identifies a hazardous item.
PMIC: Precious Metal Indicator Code. A one position code which identifies items that have precious metals as part of their content. precious metals are those metals generally considered to be uncommon, highly valuable, and relatively superior in certain properties such as resistance to corrosion and electrical conductivity.
ESD: Electrostatic Discharge. Indicates if an item is susceptible to electrostatic discharge or electromagnetic interference damage. electrostatic discharge damage occurs when an accumulation of static electricity generated by the relative motion or separation of materials is released to another item by direct contact. electromagnetic interference damage occurs when an item comes into proximity with an electrostatic or magnetic field.
ENAC: Enviromental Attribute Code. Identifies items with environmentally preferred characteristics.
CRITL: Criticality Indicator Code. Indicates an item is technically critical by tolerance, fit, application, nuclear hardness properties, or other characteristics.