Abstract: A band configured to apply a force to a physiological sensor on a portion of a user's body can include an elastic segment, a first indicator, and a second indicator. The elastic segment can have a first end and a second end opposite the first end, and a first portion of the elastic segment can be secured to a second portion of the elastic segment to form a closed loop that can at least partially secure the physiological sensor to the portion of the user's body when in use. The first and second indicators can be spaced apart from one another and positioned along the elastic segment. The first indicator can be positioned closer to the first end than the second indicator. A relative distance between the first and second indicators can provide an indication of a desired stretch of the elastic segment.