Hi, It just occured to me that if your flap opens, and closes it is at least the second design. The third design was a beefed up model with metal supports in the tail of the flap, It is supposed to hold up better on trails over bumps, and it also was pitched for use with or without the angled rail kits.
Drop me an email to ed@michigan-snowhawk.com , and I can email pictures of the different snowflaps.
Ed
www.michigan-snowhawk.com