Dan Wesson .44 SuperMag

I inharited one of these about eight years ago and was hoping someone could help me out with some information on it. How much it's worth and any other info would be highly appreciated.
Dan Wesson .44 Mag
SB0040**
Monson, Mass.
with about a 7 in. Barrel
Thats about all I got. There is no model number to be found so I don't even know what model of gun I own???