You can use it as a diaper as it is with an absorbent pad.
It can also be used as sanitary pants as a diaper cover.
The size is from 44cm to 68cm around the waist. There is rubber on the ventral side and 26 cm of velcro on the back side for easy fit, so you can adjust the size to fit the waist properly.
There is also a snap on the back side, so you can adjust the length and width.
The lining is mesh. It has a built-in absorbent pad. You can wash it and use it repeatedly.
