This is a high quality generic replacement brush roller, also called a beater bar, beater brush, or roller brush assembly designed for all Dyson DC25 The Ball Bagless Upright Vacuum Cleaner Models, and works as Dyson part 917391-01, 914129-01, or 91739101 and 91412901. Replacement part includes all components of the brush part, including the brush core, bristles, and the stainless steel ball bearing. A new roller brush should be installed for several reasons. If not regularly removed, maintained and cleaned, hair, thread, and other particles can become lodged in the bearing, causing the brush and bearing to heat due to the resistance, eventually melting the housing to a point where it no longer spins, or makes a loud grinding noise when vacuuming, if the brush stops spinning completely, or over time the bristles on the bar are shorter then .35 inches in length due to wear. Works with all Dyson DC-25 Ball Models, including: Purple DC25 Animal, Yellow DC25 All Floors (aka Multi Floor), Purple DC25 Mail Order Exclusive, and White DC25 Blueprint Limited Edition Models. Replacement Brush is made of a stronger, more durable polymer, reducing the chances of melting. Fits Dyson Part Number 917391-01.