The 9903 features a powerful 8.8 AMP motor with electronic speed control to maintain constant speed under load. The variable speed control dial allows the user to match the speed (690-1,440 ft./min.) to the application. The 9903 also features less noise: at only 84dB, it is one of the quietest sanders in its class.Makita’s 3 x 21-Inch Belt Sander, model 9903, combines power and speed with ease-of-use features and less noise for fast and efficient stock removal. The 9903 is ideal for woodworkers, carpenters, furniture makers, floor installers, deck builders and general contractors who require a best-in-class belt sander.