Wahl Professional Grooming Clippers – Wahl KM-SS Clipper is Single Speed operation 2400rpm. Both the KM-SS & KM-2 have the Powerful 45w rotary, gear driven clippers. KM-2 is 2 Speed operation: 2400rpm & 3000rpm. These Clippers are Fan cooled motor for cooler operation and longer life. KM-5 & KM-10 are ergonomically designed - excellent weight distribution at 360g. Slim styling - Slip-resistant grip on underbody for secure hold and improved handling. The two powerful speeds 3,000 and 3,700 rpm. KM-5 has a DC motor while the KM-10 has a brushless motor for longer life.