When so mounted together, base walls 3 and side walls 4 of base and cover members l0, 12 generally define a chamber 17 in which the operating component parts of electrical device 1 are disposed, as discussed hereinafter, and it is also contemplated that other fastening or mounting means, such as rivets or screws or the like, may alternatively be used in place of nut and bolt assemblies 14 to maint