[IN EAR MONITOR SYSTEM]: These ear monitors can amplify sound and have a top knob to control the volume. They offer a wide volume range, clear audio quality, and low distortion. [INTERFACE INTRODUCTION]: The design features XLR and TRS input connections with a locking function, as well as a 3.5mm headphone output. [EASY ACCESS TO BATTERIES]: The headphone amp features an innovative, tool-free belt clip design that allows you to access the batteries at any time. [MONO/STEREO MODE]: The headphone amplifier offers a mono/stereo switch function, allowing you to flexibly choose between options to meet different needs in different situations. [ULTRA-COMPACT]: The in ear amplifier has an extremely compact body and is made entirely of metal. Power Supply: 2 * AAA batteries(Not included batteries) Color: White Material: Metal Package Contents: 1 * Monitor Amplifier Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.