Lot of (150) indented hex washer head pole barn screws with bonded EPDM neoprene washer.
These 1000 hr salt spray coated fasteners are #9 diameter thread and are 3" in length with a 1/4" hex and have a 7/16" diameter rubber/steel bonded washer.
This screw has a twinfast style thread and type 17 point designed for attaching metal roofing and siding to ACQ treated lumber and works well in harsh conditions
The type 17 tip is a thread cutting screw for wood with an auger style point that helps clear chips and reduce splitting.