Number of revolutions of the motor
The speed of rotation of the motor of the clipper. The speed of movement of the blades directly depends on this parameter, and the quality of the haircut, in turn, depends on it: the faster the blades move, the faster and more accurately the clipper cuts.
Material
— Metal. High-end clippers/trimmers use a metal body. Typically found in professional models, and occasionally in semi-professional ones, a metal casing ensures remarkable durability and resistance to heavy use. However, this design substantially elevates the device's weight and cost.
— Plastic. Mostly low-cost clippers/trimmers are equipped with a plastic case. The plastic case is lightweight and easy to care for. Among the shortcomings of plastic, only low strength can be noted. If you intensively use a trimmer/clipper with a plastic case, then the working surface of the device will quickly become covered with scratches and scuffs.
— Metal/plastic. Semi-professional clippers/trimmers commonly feature a combination of metal and plastic casing. These models incorporate metal with plastic inserts. This approach maintains a high level of reliability while using plastic inserts to lower device costs and enhance user-friendliness. Clippers with combined casings are versatile for both home and salon use.