I purchased a prepacked 4" stainless steel vent kit along with some additional parts to complete the installation for a hanging furnace in my 40' x 45' hobby garage. The order was shipped immediately and arrived in perfect condition. The kit also came with their "red envelope" of installation guidelines which were very helpful. During the installation process I needed a longer pipe and that was shipped immediately as well. The folks at ACF were great to work with and allowed me to return the pipe from the kit that I didn't need. I highly recommend working with these folks and the ACF Greenhouse Company.