less energy is required for the motor to force air out

The ProShake in its name means its a great value

Clarke 500

DY-912584-01

poly nodules tightly grip scrub pads keeping them secure as the machine is running

iRobot APS 3000 mAh NiMH Battery Dyson DC59 Vacuum Parts less energy is required for[custom_html] The rechargeable APS 3000 mAh NiMH battery keeps your Roomba running at optimal performance. This battery is suitable for the following models: Roomba 400 Series Discovery Series Original Series Dirt Dog If you charge this battery with the APS Fast Charger (part # 4902), the battery is fully charged in less than three hours. If using the standard charger, a full charge requires 7 hours. For Roombas using this battery, expect up to four