Fermtech Bottle Filler
This is a tool that is a godsend. You need one inch of space at the top of your bottle to get correct carbonation. This filler does it for you and fills the bottles from the bottom. Attach your filler to your siphon hose and place your filler all the way to the bottom of the bottle. Fill it to the very top and pull it out and it leaves one inch of space at the top.