A plastic container with a rim and a lid, the rim and lid each having channels which, upon installation, produce a liquid-tight fit by means of three complementary pairs of projections from the walls of the channels. The shelf assembly includes a pair of brackets, a fixed shelf mounted to the pair of brackets, and a movable shelf. The footwell region is bounded laterally and at the top by a panel arrangement of lightweight construction which, together with the floor and the end wall, forms a supporting box for the front-end structure. The comparator compares the voltage of the first input terminal with the voltage of the second input terminal and outputs a comparison result. The golf club head comprises one or more adjustable features such as weight bars, weight screws, weight cartridges, and adjustable sole members, and preferably includes structural features such as pegs, teeth, and polymeric dampeners that serve to preload the one or more adjustable features on the golf club head and prevent or reduce unwanted vibrations when the golf club head is in use.