A kit for the musicians, to help them keep their tempo. Easy and simple to built, yet very accurate and repeatable. Save a lot of money compared to similar commercially available metronomes. The tempo can be adjusted with a potentiometer. The speaker is included in the kit. The circuit operates using a small 9V battery. Due to low current consumption it lasts a long time. Max. current: 30 mA. Output power: 0,5W.