As I remember it, it was a 1 to 1 5th gear.
It had lower ratio's in 1st.
And, if I remember correctly it did not stand up to big blocks. I think it was rated at 500 ft lbs.
Then, anothe rcompany bought them out. It may still be available through another name.
Instead of running 4.10 gears, you could run like a 3.23 but still launch good with its ratio's.