A fleece & PUL waterproof nappy cover for use over fitted nappies.
To measure for size:
R = Rise, which is the measurement from the waistband at the back, between the legs, to where the waistband will sit just below the belly button.
W = Waist, which is the measurement around the waist where you want the waistband to sit. Usually where underwear band would be.
If you put your measurements in the comments when you order, we can ensure a good fit as items are made to order.