Mixing by rotation is more vigorous than a roller mixer, typically the sample, in either tubes or bottles, are turn end-over-end. Rotators can be based on a rotisserie type design whereby a single axis is rotated and samples are attached to this by a variety of different methods. Alternatively, a rotator can take the form of a disk rotated around its central point; samples are attached to the edge of the disk, this form of rotator is less vigorous than the rotisserie style as the angle of the disk can be lowered to lessen the end over end action. Speed adjustment is available in both types to alter the severity of the mixing action. Ideal for aerating cultures, keeping biological samples in suspension and for general mixing applications including smaller samples held in 1.5ml micro tubes.