A necklace that detects user's heartbeat

This circuit board jewelry shaped like a heart is not a common jewelry; it is a geeky jewelry that shows the beat of your heart. Yes, it is a quite astonishing idea to wear a heart shape necklace that blinks as your heart beats.

This necklace uses a set of LEDs that blinks; actually these LEDs are synchronized with human’s heart beat. By wearing this necklace people around you can easily see the beating of your heart. Further explanation of this necklace is described in the video. This necklace price is just $70.

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