Not sure what size is right for you? No worries. This bathroom toilet stool includes a base and a topper to adjust the height. Quickly convert from 7” to 9” height with the included, removable topper. Squatty Potty Adjustable 2.0 Stool Details: Dimensions (with topper): 11.5"D x 17.75"W × 7.625"H; Dimensions (without topper): 11.5"D x 17.75"W × 9.625"H. Different size bodies may need their feet higher or lower than the rest of the household. Solution? An adjustable toilet stool with two pieces: the base and the topper. Younger children should use a 9" Squatty Potty (with the topper added on the base) while teenage squatters and adults tend to prefer the 7" stool height (without the topper). It’s the perfect adjustable toilet stool for adults that can be shared by the whole household.