Stamp on the case:
PTC10-700-27NLU-S200+
Yes, I ran this behind my 5857 with a 212/212 roller cam on a 4.1L.
I do not know if this is sprag or spragless. Hopefully the part number will tell you. I got it through Boost Crew, I didn't go into that detail when I bought it. I needed a 3100 stall 10", and they sold me this one. I raced it a couple years, then sent it back for a refurb and decided to go back to a lockup setup to try and cut the heat down when on track, so I put a lock-up ProTorque in the car and this has been sitting on the shelf since it came back from PTC.