Regularly the largest and heaviest of all rotary machines, self-propelled rear-roller lawnmowers are capable of leaving very neat, striped finishes to formal lawn and grass areas due to their integrated rear-roller and the extra weight that they carry. These machines are often equipped with powerful top-of-the-range engines to deal with both the extra weight that needs to be driven about the garden but also to deal with the larger areas they will cover and extra volume of grass that they will cut. To ensure that continuity is achieved whilst mowing, many models of both large and small rear-roller lawnmowers are fitted with variable-speed drive systems that can be altered to suit the operator’s own mowing preferences.