One LED serves as a battery level indicator, one flashes yellow after moderate impacts and a third flashes red for severe blows. mc10 wasn't willing to share the exact hardware inside, but we know that it's got a rechargeable battery and has rotational acceleration, multi-directional acceleration, impact location and impact duration.

ENGADGET

The vagaries of hardware, software and natural language will always ensure that exact reproducibility remains uncertain, but withholding code increases the chances that efforts to reproduce results will fail.

FORBES: Publish Your Code: This'll Cause Problems in Climate Change Research