for water drainage i have pierced small holes in the underneath and backing of it... (used a pin todo so)
its very secure, ive taken it to 175 and she doesnt move at all, this is because the piping is like a slinkee, and i made it longer than as you see it, so when is in there with the cable ties its applying pressure towards to front of the car and ud towards to cabin..
the pipe has no brand, i just asked for an aluminum pipe which is flexible..
cheers,
-JD