While the materials are all well made and sturdy, if you get the instert for the wall mount, it will need to be modified, which is not necessarily easy, I'm not sure what type of wall they used to make their design, but the insert was at least 5" too wide for my wall. Had to use a jigsaw and grinder to get it installed.I purchased this door over a year ago. I have three very active dogs and they come blasting through the door all the time. The flap developed a small tear at the top, so I ordered a replacement flap which was promptly sent out to me. When I received the flap I noticed it was different than my old one. I contacted the company directly and they told me I had a older model door and that the new style had improved upon the design of the door and flap. I was fully prepared to order the new style and the company told me they would send me a replacement door at no charge and I could keep the flap I bought as an extra. I am still shocked at the amazing customer service Extreme Dog door provided. No body does that these days. In fact I just ordered another door for my sons house because of the excellent customer service and returned the other brand he had purchased. Definitely buy this product you will be very satisfied. They rock!!!!!!!!!!!!!UPDATE: 8/17/2020I was getting ready to purchase a new set of flaps when I read in their on-site reviews that they had updated the design/materials and that they were replacing the old flaps for free. I called. Super friendly guy answered. I told him what had happened and he sent two new flaps. I'm obviously hoping the flaps will be much better quality, but the service was impeccable. I'm guessing the new flaps are what now ship from Amazon, so you should receive a solid set of flaps.ORIGINAL REVIEW:The framing is good, sturdy, and seemingly well-made, but the flap material is negligently flimsy. I installed the door in September 2020. The outer flap failed in November, so I used some liquid nails to hold it in place for the winter. Both the inner and outer flaps failed on a freezing day, the temperature somewhere in the teens (Northern Colorado). Now I have a gaping hole where I must consistently purchase flap replacements for $40, possibly as often as twice a year. Normal wear and tear. Two pups. Installed exactly as laid out by the provided instructions. Absolutely worthless. The next letter is to the better business bureau over fraudulence in advertising; it does NOT hold up to the cold and it does NOT hold up to normal wear and tear. While I wish there were a better alternative, I could not find one at the time of purchase, I can tell you that if you live anywhere that gets even a little chilly, do NOT buy this dog door.You have options like removing 1 or both door flaps, solid construction, tunnel cut to fit depending on thickness of wall etc.While the components seem quality the aluminum plates that are intended to be in the wall are ridiculously wide. I honestly think they would be too wide for 2X6 construction and completely useless for 2X4 construction the door would have to stick out over 2 inches on one side. They are vary sturdy so I don't have anything that could attempt to cut them. This made the inside of the tunnel look unfinished. Door seem nice.Was not easy to install.The seller information indicates an, "expanding tunnel." The rigid metal tunnel is made for an 8" thick wall only, four 8.5" wide tunnel sections. This is the only wall installation dog door I know of that isn't made to easily adapt for varying thicknesses. There is no mention of this on their website or in the installation instructions. The only instructions are for the through-the-door unit. I called customer support and they offered no answers or additional instructions.The only way to reduce it is by cutting through the metal sections, good luck. If you have the right saw, and decide to try and adapt it, measure your wall thickness and add a 1/2." the extra 1/2" allows the box to insert into the exterior entry panels.You may want to consider buying the door entry version and buying a sheet of 3/16" x12"x24" plastic, about $12 bucks on ebay, for your tunnel, much easier to cut, . Easier to install and a net savings.P.S, Extreme Dog Door is still the best dog door available for the money.Had to trim down for the wall thickness, good to know it works on a 2x6 construction home. Had to work it a little because the outside was square with the flap but the flap still didn't touch bottom, the inside was off square. There also is no seal where the magnets are so some breeze does get by.