I purchased and installed 8 pieces of the simpson pellet vent pro pipe and wall thimble. It all assembled easily. The instructions say you do not need to seal the joints of the pipe, I didn't use any and my vent is leak free. I extended the pipe 18 outside the wall of my house and have not had any ash accumulation on the white vinyl siding. I also bought the stove adapter, but it did not fit my exhaust outlet very well, so I used a 6 extension piece of provent pipe. It fit much better-you do use selant on the piece you connect to your stove. I didn't know the outlet piece was stainless steel, so if you use an extension piece to get it away from your siding, you may want to consider getting the extension piece in stainless so it will match. Overall very happy with my purchase.