I am sitting here reading through my manual that came with the pipe when I got it and now I am just flat out confused. I have the plain and simple pellet vent not the pellet vent pro. On the stickers that came on the pipe it says 1 inch min to combustibles, but on the site I bought it from and even the simpson dura vent site says it's 3 inches min to combustibles for the USA. In the simpson dura pelletvent manual that came with the pipe claims to even say 1 inch min in USA for pellets, oil burning, and corn burning, but 3 inches in Canada for pellet and corn. Also on the sticker that is on the pipe says not for use with cornburning appliances, but says you can burn corn with this pipe?? Freaking confusing! Anyways I already have the pipe in through the wall with the thimble and it gives it a 1" radius from pipe to the outside wall. I just measured. So anyone have thoughts?