Wide Compatibility - Perfectly compatible with all iRobot Roomba 500, 600, 700, 800 and 900 series models.,Enhanced Design - Bearings allow the wheel to spin easier and reduces the amount of debris that breaks down functionality over time.,Easy to Assemble - Cut and remove worn rubber tires, place new tires. Easy to replace front casters, snaps in place, no tools required,Package Includes - 2 x front castor wheel and 2 x Tires,Efficient Service - If you have any questions, please feel free to contact us, we will serve you wholeheartedly.