Somewhere on the road I lost one of the two bolts that hold my exhaust pipe to its hanger. I've since found that the replacement bolts I picked up work a factor of 3.5 better than the stock bolts.
M8 1.25 x 20 socket head cap screw (comes in a pack of two from Lowes)
The cap head makes it a lot easier to hand thread the bolts through the hangar into the pipe. This is a real time saver if you're in the process of banging out the baffles, one by one, from your pipes.