The "DOS" series dosing units for volumes of 250, 500, 1000, and 1500cc are devices suitable for filling viscous and non-viscous liquids for the food, cosmetic, chemical, and pharmaceutical industries. They consist of a pneumatic drive part, a dosing part where the product is drawn in and dispensed, a rotary valve with clamp-type connections and a related pneumatic actuation cylinder, and a gravitational handwheel for adjusting the amount of fluid to be dosed. The valve and dosing part are easily removable for proper and thorough cleaning of the areas in direct contact with the fluid. The available accessories allow for the possibility of having pneumatic limit switches to automate operation and a kit for dosing liquid consistency products. For applications with volumes less than 150 cc, a simplified version has been designed without a rotary valve but equipped with a clamp connection to mount the VU2 accessory or another dispensing mechanism provided by the customer.