Left two buttons are used to adjust volume.Right two buttons are used to switch stations. The switch on the side is the switch. UP is ON and is OFF. It is a simple receiver and can be used all over the world with by 18650 rechargeable battery. It is very suitable for users to learn electronic circuits, practice and proficient soldering skills, and enhance electronic professional knowledge and interest. Universal frequency 87MHz-108MHz Perfect simple circuit DIY hand soldering Stable fixing bracket Support battery charging function Product Name: RDA5807 Radio Receiver DIY Kit Work Voltage:DC 3.7V Type:(Not Included ) Work Temperature:-25~85 Work Humidity:5%~95%RH Material: pcb colour: green Package Contents: 1 x Radio DIY Kit Only the above package content, other products are not included. Note: Light and different displays may the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.