Abstract: A multi-module wearable device. According to an embodiment of the present disclosure, there is provided a system, including: a first wearable instrument; a second wearable instrument including a biometric sensor; an electrical connection between the first wearable instrument and the second wearable instrument; and a strap, sized and dimensioned to be disposed about a wrist. The electrical connection may be capable of connecting the first wearable instrument to the second wearable instrument when the second wearable instrument is at a first position on the strap relative to the first wearable instrument, and of connecting the first wearable instrument to the second wearable instrument when the second wearable instrument is at a second position on the strap relative to the first wearable instrument.