Approximately 19 inch radius, 22.5 degrees - meaning it takes sixteen pieces to make a 38 inch circle. This is track compatible with Blackstone's Protraxx System. NOTE: rail height is slightly taller so there will be a slight bump between sections of my track and theirs. I have tested this with numerous locomotives from Blackstone, Con-Cor, Valley Locomotive Works, and several brass locomotives and none had issues. You get one curved section and three 1in tall bents that can be placed anywhere on the piece between the connections. These are FDM printed in two colors using the best printers on the market but the are still not nearly as robust as injection molded. Look at my other auctions for more track sections and turnouts to complete your layout.
eBay