- A. Bowl length: measure from the centre of the two seat bolts to the very front of the bowl. Most round bowls are about 16.5 in and most elongated bowls are about 18.5 in. Choose the seat shape that matches.
- B. Bolt spacing: measure centre to centre between the two bolt holes.
- C. Room behind the bolts: measure straight back from a bolt hole to the tank or toilet body.
- Power (electric seats): make sure a grounded outlet is within reach of the seat’s power cord.
Each seat model has its own limits for B and C. Check the product details or the owner’s manual. Not sure? Send these three numbers with your toilet’s make and model to [email protected], and we can help you check the fit before you order.