An incredibly versitle little streamer, the Beaver Bugger is a jigged style fly with a tungsten bead and lead wraps underneath to get down quick. The size 8 is good for faster or deeper water, and the size 12 gets the nod in slower skinnier water. These fish great either stripped/jigged back to you, or twitched and dead-drifted under an indicator. 
P.S. - Don't sleep on these for smallmouth in our local creeks - they love them!