Anybody thinking about this model it does not come airtight. The 300 is wicked tight. This new one just did not seem tight after some checking I found the lid and the doors to have a bit of an air gap. I got some Food safe foam tape and spent a little time sealing it up. It is now well sealed. If you don't lock the bottom doors and let the lid drop the pressure will pop them open. If you close the bottom door to fast it will cause the lid to jump up. It is good to go now.