The invention recites an apparatus comprising a nozzle holder able to retain at least one nozzle and disposed on a pressure washer wand. An exemplary method of making a liquid or gel suspension of diodes comprises: adding a viscosity modifier to a plurality of diodes in a first solvent; and mixing the plurality of diodes, the first solvent and the viscosity modifier to form the liquid or gel suspension of the plurality of diodes. Then, the main control unit accepts an operation of deciding the button according to a release operation or long touch performed thereafter. The film portion within the area defined by the bead is tight and planar in a plane spaced from the frame and retained in that condition by the cured adhesive.