1.1 This specification covers Type 58 borosilicate sealing glass for use in electronic applications.

Note 1--This specification is primarily intended to consider glass as most generally used, that is, glass in its transparent form as normally encountered in fabricating electronic devices. X1.3 refers to a sealing alloy that is compatible with this glass. Type 58 glass in other forms such as powdered, crushed, sintered, fibrous, etc., are excluded. The requirements of this specification, as applied to these forms, must be established in the raw glass prior to its conversion.