An oximeter sensor with an emitter and a detector, and a sensor body surface having a first color proximate to at least one of the emitter or detector. The color can be modified by a user to adapt the sensor to be optimized for maximal signal strength or insensitivity to skin pigmentation variability or accuracy. In a preferred embodiment, a pulse oximeter sensor with an outer layer which is colored gray or black in the region of the emitters and detector and in between can be peeled-away to reveal a substantially white layer. Alternately, a white colored layer could peeled-away to reveal a gray or black layer. Alternately, more than one peeled-away layer could be used to provide a range of colors.