Share 'Can you help me identify this disc?'

I bought this disc off ebay a couple of days ago. ive thrown it a couple of times and it seems pretty stable . The bottom has a very shallow rim with a bead that kinda feels like a roc. The flight plate on top is completely flat. Its a lower grade plastic like dx or pro d. This disc is stamped with river city flyers team challenge from sept. 25th 2004. Anybody attend this tourny or know what this…