Thanks for any tips if this is dangerous.

Dean

There are around 15,000 residential fires related to dryers each year,
and around 400 cases of carbon monoxide induced injury or death
related to defective dryer exhausts, so incorrect installations of
these needs to be taken seriously.

1) The posters above are correct, no screws.

2) Male end of each section of pipe toward runs FROM dryer INTO next
section toward exterior.

3) Check dryer' manufacturer's instructions for maximum run exhaust,
which is reduced by each elbow .

4) Dryer exhaust below a deck can shorten life of wood decking, it can
also GREATLY accelerate rusting of joist hangers and lag or other bolts
connecting the deck to the main structure, leading to structural
failure. If you MUST exhaust at this point, use SS hangers and
fasteners.

5) Clean the duct, regularly GOGGLE for "dryer exhaust brush"