Electric Interval Timer Model 300 (Black)

Ideal for photographic, graphic arts, and printing darkroom use. Provides 60 minutes of timing by minutes and seconds in one-second increments. Buzzer alarm with variable volume control signals end of time period. Black face has a single circle of interval time numerals. Hands and numerals are phosphorescent. With two three-wire outlet receptacles. Chemical- and moisture-resistant case is made from a blend of hybrid plastics.