This red top-mounted button allows you to quickly pause mixing while you add or remove tubes. This handy feature extends the life of your rocker as you no longer grind gears while removing tubes. Newly redesign side panels add stability to the unit while retaining the small-footprint on your benchtop.. Heavy duty and silent mixer. 15 tube capacity. 25 rocking cycles per minute speed. Reversible and autoclavable pad. . UNICO L-TTR200 Model Rock-IT Tube Rocker with Pause Button, 15 Tubes/Vials Capacity, 25 cpm, 110V. L-TTR200. Country of Origin : United States.