The Chase G Super Flat Fork is made with a traditional axle to crown dimension, while the other Flatware Forks had a shorter dimension to decrease the amount of space between the steerer and tire. The Super Flat also has the foreskin to bring the steerer as close as possible to a 1.75" tire as possible.
Worth noting, these forks were designed to be flat specific, so I am not sure how they would hold up for street riding.