US Patent 8726945 Chemical dispensing reservoir apparatus and methods

Removable chemical reservoirs are translucent and have filling marks on a front, hollow handle where chemical concentrate fill levels are visible and measurable. The reservoirs are filled with new concentrate from a current fill level mark to a full level mark and the volume of concentrate filled between the marks is calculated for filling and inventory purposes. The front handle is narrower than the reservoir sides and flanges at the upper end of the reservoir to facilitate in and out sliding of the reservoir for billing and cleaning.