The CV986 is a protective gas-filled spark-gap designed to break down at 250 Volts and can pass a maximum current of 15 Amps. The function is as a lighting arrestor.
Brass end cap with soldered connection.
The domed electrodes are held in a pinch. The envelope will have a low pressure gas filling.
The thin glass tube envelope is 19 mm in diameter and, excluding the base connections, is 68 mm tall.