TOTO Bathtub Drainage Push button switch , bathtub pop-up waste chrome DB505R-3A , fits bathtub with depth from 500-570 mm

This type of switch is designed to control the opening and closing of the bathtub drain to allow water to enter or exit the tub.

Instead of traditional drain plugs or levers, some modern bathtubs, especially those with innovative designs, feature push button switches for drainage control.