Attached to water bottle contain cleaning solution, no need to move cleaning detergent
Having to move cleaning detergent everywhere, takes a lot of effort
Hold round water bottle and comfortably rub dirty area
Flat handle and if you rub it for a while, it will burning sensation and painful
Spray solution & brush continuously with just one hand, saving effort and time
Inconvenient to have to constantly switch hands to spray solution and then brush again
AND Ordinary brushes are hard to reach into the gaps, soft bristles are not strong enough to clean, more difficult