The Old Town Canoe Snap-in Center Seat snugly snaps over vinyl gunwales and stays in place until you pop it out. It provides an easy and quick way to add a third seat to tandem canoe. The Snap-in center seat fits in the middle of all Old Town Canoes with widths of 34" to 37". The rugged design can hold an adult or two children and carries up to 300 lbs. Consider a snap-in seat, oar sockets and oarlocks and you have a rowing canoe.
Have a Coleman canoe I used this on--its 37 inches wide. Fits just fine. Price was the best I could find anywhere on the web. Delivery was fast.
Bought this for a 1971 Gruman canoe works great