Ultra quiet machines, as low as 63 dBA, ensures safe sound levels. Active filtration with HEPA standard, maintains indoor air quality. 90 degree flip up head, enables a safe ergonomic position when changing pad. Pad motor: 36V, 90 A, 3.6 hp max; Pad speed: 1875 rpm. Burnishing speed (variable): Min 100 fpm, max 200 fpm.