The GM-1 is an ultra-compact metronome that you can attach to one ear just like a handset. When you use multiple GM-1 devices, everyone will hear the same, so everyone can train in sync at the same pace. Therefore, GM-1 can be used to rehearse groups such as marching bands or dance groups, or for rehearsals where you need to move. The channel-type earring unit sits comfortably and safely on your ear, and thanks to it, you can clearly hear the sound of the metronome in the surrounding noise. The GM-1 is ideal for achieving that perfect moment when everyone fully feels the right pace and rhythm, so all teammates and colleagues remain in sync throughout the performance. A metronome that synchronizes the tempo in multiple units - ideal for group rehearsals. It fits perfectly on the ear - suitable for exercising on a musical instrument when you need to move. The channel-type earphone unit brings the sound of the metronome directly into your ear, so you won’t get lost. It offers a wide range of beats and rhythms - even an irregular meter. Use the jog switch for an intuitive pace. Low consumption - endurance of about 100 hours of continuous operation. Memory backup feature that automatically saves your previous settings. Three sizes of earring unit (S, M and L) in a package. Package Quantity (pcs): 4Type: DigitalDisplay: YesColour: BlackMaterial: PlasticTempo: 30-252Battery Operation: YesBattery Type: Lithium CR2032UK/EU Power supply included: NoPower Supply: None, Only Battery OperatedBundle: YesPackage Contents: BatteryPackage Contents: ManualPackage Contents: EarpieceDepth (cm): 2.2Width (cm): 4.9Height (cm): 2.2Weight (g): 9.0Made in: ChinaPackage Contents: Earplugs