15" from the center of the bottom bracket to the top of the seat tube front, 14" rear. Says STING RAY MINI TWINN on the chain guard.Please feel free to contact me with any questions. The item "Vintage SCHWINN STING-RAY MINI-TWIN Tandem Muscle Bicycle" is in sale since Saturday, September 14, 2019. This item is in the category "Sporting Goods\Cycling\Vintage Cycling\Vintage Bicycles". The seller is "fastrubberboat" and is located in Edgecomb, Maine. This item can be shipped worldwide.