Hand-operated turntable produces nearly concentric circles of evenly distributed bacterial colonies. This turntable will accommodate three different sizes of Petri dishes -- 60, 90, 100mm. Ball bearings ensure smooth and effortless spinning for faster and more accurate inoculation. The turntable is lightweight and portable. The recessed non-skid neoprene turntable top keeps the Petri dishes in place and is removable for cleaning; replacement pads are available. The body of the unit is rugged and easy to clean polypropylene. Dimensions: 5 x 2.5", Weight: 14.3 oz.