8-18 x 3/4 Phillips Indented Hex Washer Self Tapping Screw Type B Fully Threaded Zinc D6923188 It has a nylon insert

It has a nylon insert that helps to prevent loosening due to vibration or movement

and the coarse thread ensures a secure hold

which provides a secure grip for tightening

and a 16-inch length

8-18 x 3/4 Phillips Indented Hex Washer Self Tapping Screw Type B Fully Threaded Zinc D6923188 It has a nylon insert8 18 x 3 4 Phillips Indented Hex Washer Self Tapping Screw Type B Fully Threaded Zinc are designed for use in metal applications. They have a Phillips drive and a hex washer head. The self tapping design allows the screw to create its own threads as it is driven into the material. The Type B point is designed for use in thicker materials. The fully threaded design provides maximum holding power. The zinc coating provides corrosion resistance.