The bit can be very helpful and effective in curbing picking behavior, but a few words of caution.
Keep an eye on how he's eating. He should have no trouble, but some chickens are so intimidated by the bit, they refuse to try to eat.
The other problem is you need to watch his beak tip. The tip is protected by the bit from natural wear, and I've seen a beak grow long and begin to crowd the bit. You may need to remove the bit after several weeks and trim the beak tip, just snipping off the tip of the upper beak.
Another thing to look out for is breakage. The black color absorbs solar radiation and deteriorates, resulting in breakage. That's also happened to me, and I didn't even notice it because the bit was still in place, just the end part that keeps the beak from closing was missing.
I doubt you'll see anything in the instruction manual about these things, if there is one..
But like pinless peepers, some chickens manage to work around the bit and resume feather picking. So monitor his behavior.