As of July 3, the iRobot Roomba Plus 405 is on sale for $399.99. This deal saves you $400 on list price, and is the lowest-ever price according to camelcamelcamel. Our robot vacuum expert has hand-picked this deal as one of the best ahead of Prime Day.

Don’t stress anymore when you get home about having to mop and vacuum. You should enjoy a clean home when you get back from a long day of work, a nd the iRobot Roomba combination mop and vacuum can make that happen for just $400—a 50% discount for Amazon Prime members.

Starting July 8, Prime Day will run for four days with deep price cuts on smart home gadgets, including the Roomba Robot Vacuum and Mop Combo from iRobot that drops down to an all-time low of $140 from its original $275 price tag.