Abstract: A trailer comprising an open top rectangular box member which is detachably attachable to a support assembly which is attachable to a motor vehicle so that the trailer can be towed. The support assembly comprises a support member mounted on two wheels, the open top box member being attached to the support member when the trailer is ready for use and detachable therefrom when the trailer is not in use. The support assembly is, when detached, locatable within the open top box member so that the support member at least substantially closes the open top of the box member to thus form a box-like structure which can be stored resting in any desired face.

Abstract: Method for preparing aluminum, especially large aluminum pieces or articles having a surface layer of aluminum oxide for subsequent metal plating wherein the aluminum or aluminum alloy substrate is immersed in a bath containing metal salts and acid such that the acid content relative to the metal salt is sufficient to remove the surface aluminum oxide layer without substantial attack on the underlying aluminum while enabling the permanent deposit thereon of a continuous, smooth, adherent metal or metal alloy coating directly onto the aluminum, thereby replacing the aluminum oxide layer. Subsequent, essentially blister-free electroless or electrolytic plating of nickel or a nickel alloy, copper or a copper alloy onto the metal or metal alloy coated aluminum are made possible thereby.