An electrophotographic image forming device includes a replaceable unit having a housing that includes a top, a bottom, a front, and a rear positioned between a first side and a second side of the housing. The housing has a reservoir for storing toner. A rotatable shaft is positioned within the reservoir and has an axis of rotation. A magnet in the reservoir is movable in response to rotation of the shaft. An engagement member is positioned on an exterior of the top of the housing. The engagement member is aligned with a point in a path of movement of the magnet in the reservoir. The engagement member has a front surface that is unobstructed to contact and push a housing in the image forming device supporting a magnetic sensor to an operating position of the magnetic sensor during insertion of the replaceable unit into the image forming device.