Estimate the dosing of alums & such other coagulants for treatment of water & effluent. Samples are easily viewed by diffused base illumination with fluorescent tube placed below plastic plate & black background. Fitted with D.C. motor of 1/20 HP with variable speed up to 50–100 RPM controlled by speed regulator. Provided with stainless steel paddles with adjustable spacers to adjust the depth of paddles. (Supplied without glass parts).