This power module is an extension board for your micro:bit, powered by two batteries so you can use your it anywhere you want! There's also an onboard buzzer that you can use as an extra output. For instance; to make your micro:bit buzz when it starts up!
Features:

1. export micro:bit® pins P1, P2, 3V & GND
2. onboard buzzer controlled by micro:bit® P0 port

Specifications:

1. working voltage: 2.7 V - 3.3 V
2. battery: CR2025
3. dimensions: 42 x 52 x 5 mm

vmm005_a4v02.pdf