The SR 4 is an external controller for RPM22, RPM44, RPM88 with a rotary data encoder equipped with a 31-position LED indicator. The encoder can be pressed like a button. Additionally, the SR 4 features a column of eight LED diodes that inform you of the value you are currently adjusting. Labels can be easily created and inserted under the plastic cover. Pre-printed cards for these labels are included in multiple colors. The SR 4 features a 31-position LED indicator, rotary data encoder with an integrated push switch, and a column of eight green LED indicators for selection status. Custom selection lists can be effortlessly created using the provided Microsoft Word template or the SR 4 Label Maker application. The list is then placed under the transparent window of the SR 4's faceplate insert and secured by a plastic lens. Each SR 4 comes with three faceplate inserts: white (with black logo), almond (with black logo), and black (with white logo).