Portable flocculator that allows standard conditions to be adopted for jar test, that are the basic requirement for reproducible results. The FP4 is a multiple stirrers with reproducible stirring speeds allowing standard conditions to be met during analysis, a basic requirement in order to obtain reliable and repeatable results. It is a portable model with four stirring places, designed to be used on-site, as it can be powered by a battery or a car cigarette lighter. FP4 has been manufactured with a strong metallic frame with an epoxy painting purposely studied to offer a high protection degree against chemical and mechanical corrosion. The stainless steel stirring rods are adjustable in height by a self blocking chuck, whilst the anti-skid base ensures improved stability. Rotation speed is controlled by a gear motor powered by direct current controlled electronically by a microprocessor. From the front panel its possible to select the stirring speed through selectors (20-40-50-100-200 rpm) and the operating time for unattended operation. The four stirring points are arranged in a circle around a light to offer an easier control of the flocculation process. The state-of-the-art technology ensures maximum convenience and makes the unit maintenance-free.