The Musicians 9V Cable Tester by Boston is a portable device designed to test 6.35mm 1/4" jack TS-TRS audio cables. With a 1:1 connection split/duplication, this cable tester features two 6.35mm jack female connectors, one for input and one for output. The tester operates at a 9V output voltage and comes with a 1-year manufacturer warranty. Made in the Netherlands, this black-coloured device is essential for musicians and audio professionals to ensure/check the quality of their audio cables.