slim 4-pole audio curly cable, black: 4-pole 3.5 mm stereo (trrs). use this cable to enable microphone input from headphones, for example the M-1, to compatible devices such as most smartphones or the OP-Z. slim audio cable curly, gray: 3.5 mm stereo (trs). use this cable as a regular audio cable or to sync for instance the pocket operator with the modular system. length: 1200 mm. slim audio cable regular, gray: 3.5 mm stereo (trs). use this cable as a regular audio cable or to sync for instance the pocket operator with the modular system. length: 750 mm. slim audio cable angled: 3.5 mm stereo (trs). use this cable as a regular audio cable or to sync for instance the pocket operator with the modular system. length: 1500 mm.