A simple analog four-quadrant function multiplier has been developed on the well-known quarter-square principle to explore the possibilities of using Raytheon type QK-329 beam deflection square-law tubes as the square-law circuit elements in this application. A frequency response flat from dc to 90kc, accuracy within +̲ 0.5 percent of maximum product, and long-term stability within 1 percent were achieved with this relatively crude model. Present limitations on this multiplier's performance are imposed primarily by the associated linear circuitry and not by the square-law tubes. Sizable increases in bandwith, accuracy, and zero stability are achievable with existing square-law tubes by improving the associated circuitry.