An illumining device includes a base, lamp, and a clip. When a denitration unit is not used, performance to remove mercury from a boiler waste gas is reduced. The barrel-receiver assembly is movable between an open position and a closed position. A plurality of rotating elements is provided, each rotatable about a primary axis, wherein each of the plurality of rotating elements supports at least one magnet, wherein each of the magnets is located along a common plane. ARCs of the invention exhibit exceptional conformality upon application to a substrate surface. A practical embodiment has a friction shoe engaged for vertical displacement by the first spring which is mounted on a side frame and the second spring is obliquely arranged between the bolster of the bogie and the friction shoe, which has guides to cause it to move into greater frictional engagement upon load being applied through the spring.