An incubator shaker (or thermal shaker) can be considered a mix of an incubator and a shaker. It has the ability to shake while maintaining optimal conditions for incubating microbes or DNA replications. Generally, an orbital shaker works by generating a circular shaking motion at a slow speed of 25-500 rpm. The shaker contains an oscillating board that holds the vessels as the device shakes to agitate or mix the substances in the vessels.