The INGUN KS-050 30 E08 (INGUN item KS-05030E08) is a press-in receptacle for fine-pitch probe fields, with a press ring and a solder-cup termination. It is pressed into the fixture's probe plate and the spring probe plugs into it, so probes can be exchanged during maintenance without any wiring work.
The KS-050 body is 0.95 mm outer diameter into a 0.98 – 1.0 mm hole, but it is noticeably longer than the comparable KS-550 at 40.6 mm, with a 7.9 mm collar. That length is what you want where the receptacle has to bridge a thicker plate stack; where the stack is shallow the shorter KS-550 30 E08 is the easier fit.
Total length 40.6 mm (1.59 in), outer diameter 0.95 mm (.037 in)
Collar diameter 1.04 mm, collar height 7.9 mm; with press ring
