I don't know sealall,but According to what I can see on the datasheet,I think that the hylomar is a lot less toxic.anyway The purpose of my post is not to advertise this product,just to give a tip on a product that I find usefull.Of course PSP fittings look just fine,but for me in france the cost of the invoice reduces the interest of the product,so I prefer to make my own cap with fittings and a good sealant,happily I can find fiji bottles here and the half liter one will make a perfect tank for my new extreme flight edge 88"