An assembly for attaching and detaching a module to and from a base, the assembly comprising: a base, a module removably attachable to the base, and a feedback system; the base comprising a rigid wall and the module comprising a housing defining an interior volume of the housing, the housing comprising a rigid outer wall, the housing wall relatively movable against the base wall when attaching and detaching the module to or from the base, the base wall and the housing wall cooperatively guiding said relative movement of the module with respect to the base along a first longitudinal axis; the feedback system comprising a spring arm and a groove, the spring arm attached to one of the base wall and the housing wall, the groove in the other of the base wall and the housing wall, the spring arm being elastically deflectable from a neutral state of the spring arm, the spring arm comprising a follower at an end of the spring arm, the groove extending along a second longitudinal axis being parallel with the first axis when the base wall and the housing wall are guiding relative movement of the module with respect to the base, the groove being defined by a sidewall extending along the second axis, first and second spaced-apart cams (38, 40) extending into the groove from the sidewall; the follower being received in the groove when the module wall and the base wall are guiding relative movement of the module with respect to the base, the follower moving in an insertion direction with respect to the groove when attaching the module to the base and moving in an extraction direction with respect to the groove when detaching the module from the base; the follower successively moving against the first cam and then moving against the second cam when detaching an attached module from the base wherein each cam (38, 40) deflects the spring arm away from the neutral state of the spring arm during detachment of the module from the base; the follower successively moving against the second cam and then moving against the first cam when attaching a detached module to the base wherein each cam (38, 40) displaces the spring arm away from the neutral state of the spring arm during attachment of the module to the base; the first cam being shaped to deflect the follower a first maximum deflection and the second cam being shaped to deflect the follower a second maximum deflection different than the first maximum deflection; whereby deflection of the spring arm during attachment or detachment of the module generates tactile feedback to the operator of the relative position of the module with respect to the base during attachment or detachment of the module to or from the base. a base, a module removably attachable to the base, and a feedback system; the base comprising a rigid wall and the module comprising a housing defining an interior volume of the housing, the housing comprising a rigid outer wall, the housing wall relatively movable against the base wall when attaching and detaching the module to or from the base, the base wall and the housing wall cooperatively guiding said relative movement of the module with respect to the base along a first longitudinal axis; the feedback system comprising a spring arm and a groove, the spring arm attached to one of the base wall and the housing wall, the groove in the other of the base wall and the housing wall, the spring arm being elastically deflectable from a neutral state of the spring arm, the spring arm comprising a follower at an end of the spring arm, the groove extending along a second longitudinal axis being parallel with the first axis when the base wall and the housing wall are guiding relative movement of the module with respect to the base, the groove being defined by a sidewall extending along the second axis, first and second spaced-apart cams (38, 40) extending into the groove from the sidewall; the follower being received in the groove when the module wall and the base wall are guiding relative movement of the module with respect to the base, the follower moving in an insertion direction with respect to the groove when attaching the module to the base and moving in an extraction direction with respect to the groove when detaching the module from the base; the follower successively moving against the first cam and then moving against the second cam when detaching an attached module from the base wherein each cam (38, 40) deflects the spring arm away from the neutral state of the spring arm during detachment of the module from the base; the follower successively moving against the second cam and then moving against the first cam when attaching a detached module to the base wherein each cam (38, 40) displaces the spring arm away from the neutral state of the spring arm during attachment of the module to the base; the first cam being shaped to deflect the follower a first maximum deflection and the second cam being shaped to deflect the follower a second maximum deflection different than the first maximum deflection; whereby deflection of the spring arm during attachment or detachment of the module generates tactile feedback to the operator of the relative position of the module with respect to the base during attachment or detachment of the module to or from the base.