Picture two shows the serial number. I believe this confirms the frame size of 54.5cm. The item "Vintage 1990 Cannondale Black Lightning Hand Crafted 54.5cm Bike" is in sale since Sunday, March 21, 2021.This item is in the category "Sporting Goods\Cycling\Vintage Cycling\Vintage Bicycles". The seller is "llpwtw" and is located in Nashville, Tennessee. This item can't be shipped, the buyer must pick up the item.