how many miles are on ure car? if you are still within the break-in period, this probably isnt a concern, it takes a while for the freeze plugs to seal up all the way, sometimes up to 10,000 miles or so, so that may leak a bit, i just say keep an eye one it and keep it topped off. and you have to mix it unless it says 50/50 on it, but i wouldnt buy 50/50, ripoff. ure paying $6 for half the amount of coolant you would get as if you paid $8 for straight coolant, ure call tho