AEMC 2118.78 Kelvin Probes For Micro-ohmmeters, 20 Ft, 10A, Spring Loaded. The AEMC 211878 Pencil Point Kelvin Probe, 10A, 20 ft. Cable can be used with any micro-ohmmeter that has binding posts from 4mm to 6mm in diameter or safety terminals 4mm in diameter. The test probe is useful for very accurately measuring a low resistance, and the AEMC 211877 Pencil Point probe improves contact by removing a thin layer of rust, paint, or dirt. When the user presses on the probes, they rotate as they retract. Measurements are made in 4-wire mode, making lead resistance compensation unnecessary. The AEMC 211878 probe is thicker, allowing for more "rugged" usage.