Thank you for your review. We're sorry that the Plastic Pet Door hasn't met your expectations.
We include nylon screws with our doors for several reasons. The screws have to be cut to size to match the depth of your specific door, and it is both easier and safer to cut nylon screws rather than metal screws. Metal screws may also damage the frame if over-tightened.
In addition, the nylon screws were used in the place of metal screws because, during the initial testing of the doors, the nylon screws were found to hold up longer than the metal screws. This is because, when pets go in and out of the door many times, or when the outside temperature shifts from hot to cold over time, this can cause the frame of the door to shift slightly, expand, or contract. With metal screws, this began to cause damage to the door and the screws over time due to the fact that the rigid screws were unable to bend or shift just slightly and would tend to break after a long enough span of time, while the nylon screws have just enough “give” in them that this did not affect them.
If you have any further questions or concerns, please feel free to contact our Customer Care Center at 1-800-732-2677, and we'll be happy to help.