self drilling screw with washer

Another important factor to consider is the size and length of the screws. The size and length of the screws should be appropriate for the thickness of the material you are screwing into. If the screws are too small or too short, they may not be able to hold the roof in place properly, which can lead to leaks and other problems. On the other hand, if the screws are too large or too long, they may damage the material you are screwing into.

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