This is my second canner... I totally enjoy Nesco Carey canners.....now I can make double batches of wonderful home canned food...they are so easy to use...you can change the pressure valve  from black to ( Green) if you’re at a higher altitude......just make sure you have the updated manual..it has been updated ..... for (pressure canning) adding 8 cups of water...set the pressure valve to airtight after the countdown