A device (10 10 10) includes a light source (12) and a light detector (14) spaced from and in communication with the light source (12). An electronic processor (18) is programmed to compute pulse oximetry data from output of the light detector (14). A clamping member (26) is included on or in which the light source (12) and the light detector (14) are disposed. The clamping member (26) is configured for attachment to a human body part with the body part disposed between the light source (12) and the light detector (14) such that light from the light source (12) passes through the body part to reach the light detector (14). The clamping member (26) is configured to attach to the body part by transitioning from a first stable state to a second stable state via a compression force applied to the clamping member (26).
