Bottletop Dispenser, Analog-Adjustable, Organic, 5-50mL, Dispensette S, with Recirculation Valve. Dispensette S bottletop dispensers are suitable for an amazingly broad range of applications, particularly for many acids, saline solutions and organic solvents. Extremely easy filling and dispensing. Simple priming by optimized flow channels. Rapid and safe volume adjustment with internal scalloped track. Dispensette S Analog-adjustable: Rapid and safe volume setting withinternal scalloped track. Simple calibration adjustment with a supplied tool.