Schützinger Bench & Research and Development Spring-loaded plug 615191 - Schutzinger DI FK 8 S Ni / SW, The Schützinger DI FK 8 S Ni / SW is a black, spring-loaded plug designed for lab environments, offering both 2mm and 4mm jack socket compatibility. This safety jack connector ensures secure connections, making it ideal for laboratory and electrical testing applications. Manufactured by Schützinger, it provides reliable performance as a laboratory connector and safety jack plug. Schützinger DI FK 8 S Ni/SW Spring-Loaded Plug Black Screw Connection