A motorized mirror actuator is disclosed which includes a movable ramp having upwardly facing angled surfaces for urging a cam element in and out of the normal viewing position, thereby moving the rear view mirror into a position which will enable the driver to see his blind spot. The heat exchanger exchanges heat with a bleed airflow to provide a conditioned airflow. The laundry dryer is characterised in that said front supporting member comprises a portion that forms a component part of said tub. The anti-rollback assembly comprises a pair of graded brake cam structures operatively disposed adjacent wheels wherein the natural pull of gravity and the configuration of the cams operate to allow passage of wheels in both directions when on flat surfaces and in only a single direction when on an incline. , and the olefin epoxide is present in the reaction in a molar excess of about 10 percent over the stoichiometric amount necessary to react with the hydridoalkoxysilane. , in particular, 80 to 160\xb0 C.