Gone is the Speed Pro TT that is best known to Dahon fans as the ultimate bike for speed and aerodynamics on a foldable bike. But Dahon hasn't abandoned the spirit of the Speed Pro TT - they merely changed the name to "Vector x27h" and improved it.
The new name comes with various implications. First, it's a whole new frame. No longer is the bike built on the "Speed" frame. Instead, the all-new Vector frame is used and is supposedly supposed to be more rigid than its predecessor due to new method of producing the frame - hydroforming. This newly adopted process allows complex manipulation of the thicknesses of the tube and previously impossible shapes to be formed, allowing the frame to be stiffer yet lighter.