It's very convenient because it displays the amount you've pressed the volume pedal. There are no noticeable scratches. Velcro is attached to the back. A cable is also included. Thank you. Limetone Audio Illuminate Box Official description below: The Limetone Audio volume pedal with illuminate link function, and by connecting to a BOSS volume pedal, the amount of volume pedal depression is displayed with LEDs. By using the illuminate box mini, you can visually confirm that the volume setting is as expected, or you can grasp the current volume setting without placing your foot on the volume pedal. It is small at 3.9 x 9.8 cm and can be placed in any position within the board, in an easy-to-see location. By switching the internal MODE switch, it supports 30L, 500L / 500H respectively. * Connection to the volume pedal uses a stereo standard cable (included). * When connecting to BOSS FV-500L/H, connect this unit to the EXP terminal. * When connecting to BOSS FV-30L, use an insertion cable (Y-shaped cable) and connect the RING of the cable to the INPUT of the FV-30L and the TIP to the OUTPUT. * The names of BOSS and BOSS products are registered trademarks or trademarks of Roland Corporation. The brightness of the LEDs can be adjusted with the brightness adjustment knob.