This stuff looks like it stinks. You might end up breathing a lot of stinky fumes. Do you do a lot of cutting? I end up getting partial cans of tap magic or dark cutting oil at garage sales that last quite a while. In fact, one good pork roast, rendered, will give enough cutting oil for a year. It stinks too, but not in the same way. I hate breathing penetrating oil or military gun oil fumes. If you have a huge amount of cutting to do and need gallons of fluid, soluble cutting oil is great, but you can't leave it sitting on the machines.