Sounds like you have the older one we first usta sell 2-3 years ago. The nickel plated brass is just a newer more durable version. You only want 1 in the system. But the insides of each do work the same and both are check valves.

E85 if very bad for these. E85 contains 15% gasline in it, which will destory the seals. You can run E100 or M100 (methanol) for alcohol injection, most people mix them down to 50/50 with distilled water.