The custom RS-USB cable allows to connect the FSSB-R3 Lighting and the MKII ULTRA to the computer through the internal socket type 5-way connector (JST ref: B5B-PH-K-S) that they include. All the FSSB-R3 Lighting sold since June 2022 and the MKII ULTRA have this extra USB connection. The RS-USB cable is 1,8 m long and consists of a USB A-male connector for the computer connection and a 5-way plug housing (JST ref: PHR-5) for the internal header socket assembled on the FSSB-R3L.