Bel-Art Inoculating Turntable for 60 to 100mm Petri Dishes; 5 x 2 in. (F40913-0000) Equally allocate bacteria across Petri Dishes with ease Ball bearings assure simple and graceful spinning Lightweight, non-skid, durable and portable Manually moved turntable creates virtually concentric circles of uniformly spread out bacterial colonies Ball bearings provide a steady, even, and prolonged spin time resulting in a rapid inoculation step and extended operating life