Smaller than factory for easy install and maintenance. I feel like the factory filter does filter better, which I'm sure it does. Easy way to get rid of backfire screen, instead of hacking out the screen.
I've tried others, and they are a mess. This stuff is biodegradeable, and it cleans off easily with the powder. The grease is really thick and works well. I used to use high temp grease, but this stuff cleans easier.