A first device is attached to a second device, particularly first and second radiators, using a retainer and a cooperable button. The retainer has a base and a stem projecting from one side thereof with an elongated ratchet for engaging at least one pawl in an axial opening of the button. The button, preferably a single piece, has a hub with an axial opening in which the pawl is located and has a resilient rim. In one embodiment, side-by-side devices are embraced between the base and the button. In another embodiment, one device is embraced between the base and the button, and the base has a superstructure for engaging the other device.