The 973582100 is a 4 mm test jack from Altech/Hirschmann designed for testing PCB boards during operation. It features nickel or gold plated brass construction with a flexible, shatter-proof insulation sleeve and a solder terminal rated for maximum 2.5 mm² wire cross-section. The jack conforms to DIN41649 dimensional standards and is classified as CAT I contact type with D/C current rating capability. The device operates across a wide temperature range and is suitable for test and measurement applications requiring reliable electrical contact and mechanical durability. Common applications include in-circuit testing, PCB board diagnostics, and laboratory test setups where standardized 4 mm connectors are required.