Kelvin probe. KC27: Kelvin probes (1 set = 2 pieces) with 2 stainless steel tips for 4-pole connection of low-resistance test objects, cable length 120 cm. The Kelvin probes connect low-resistance resistors (e.g. contact resistances, shunts, ...) with a resistance measuring device using four-pole technology. This compensates for the supply line resistance. KC27 consists of 2 probes with stainless steel tips. .