AMPHENOL 80C1 male panel mount connector. 80 series. 1 contact Requires 5/8 inchD hole, 5/8 inch behind panel depth.
SWITCHCRAFT 830 1/4 IN INLINE STEREO JACK, BLACK, WITH SCREWS
AMPHENOL 3 CONTACT PANEL MOUNT MALE 91PC3M
This is an old Amphenol microphone connector series. The connectors are designed primarily for audio equipment but are used extensively on all types of portable equipment and test equipment.