The Black chrome Steel ZL1 Splitter Guard Washers for the Mustang GT350 are made with black chrome carbon steel and have a 45deg bevel as to not catch on objects and also glide over the road surface and not scrape the screws off the bottom of the GT350 splitter. The Mustang kit comes with 8 washers and one extra to be added in the center if the customer wants. The splitter washer kit do not require drilling, the screws provided will self tap into the bottom plastic of the belly pan. (self drilling screws provided) We also provide spacer washers to install in the 4 locations with existing screw holes. The washers can be placed anywhere the owner feels the bottom needs protection.