Figure an Arduino most matches the "Other" category. To be specific, it isn't an Arduino brand, it is a DigiSpark, but the trouble isn't with the device itself. The problem is with a buzzer. I got ...

Each buzzer consists of an Arduino Pro Mini 3.3 V, a nRF24L01, ... Nice project, but with this battery, such system should last 100hours, not few. Report comment. Reply. Flute Systems says: ...