The Zahn viscometer is a portable device for quickly checking the viscosity of paint, varnish, lacquer, inks, syrups, or other liquids. The viscosity of a liquid, when measured by the Zahn viscosimeter, is expressed in Zahn seconds; that is, the time required for a denite volume (44cc) of liquid to flow through the orice in the bottom of a metal cup.

The Zahn viscosimeter (formerly manufactured by G.E.), consists of a bullet-shaped, corrosion-resistant, stainless-steel cup with a precision drilled orice. A looped handle (approximately 11-1/4 inches long) is attached to the cup. A small ring is provided at the top of the handle which aligns the cup in a vertical position when withdrawing it from the liquid being tested.