Dreame Aqua 10 Ultra Roller Robot Vacuum and Mop

Suction is measured in pascals (Pa): how hard the vacuum pulls air, and dirt, in through the floor head. A higher number means it pulls more strongly from carpet fibres and floor gaps.

The tallest step the robot can climb over by itself. A "double-layer step" is two levels one after the other, such as a raised threshold with a lip on top. The numbers in brackets show each level.

Measure your highest threshold with a ruler, and include sliding-door tracks and balcony steps. If yours is lower than this number, the robot can cross it.

The roller under the robot that sweeps dirt into the suction inlet.

The mop pad swings out from the robot's body to reach along walls, into corners and around furniture legs.

Without it, a round robot leaves an unmopped strip along skirting boards and in corners, which you'd otherwise have to wipe by hand.

After each clean, the base station sucks the dust out of the robot into a sealed bag, so you don't empty a bin every time.