Set Screws (50 Qty)In order to lock the bracket system into place, we prefer using set screws on the bottom of the bracket. We at Hovr Strong Solutions prefer to use 5 16 #18 set screws. You can, however, use smaller ones, such as 20 or # 10 24. We use a Cup point, Hex drive, Black Oxide, Alloy steel. Please note: each order come with 50 units of your choosing. WHAT'S INCLUDED Each unit comes with: 50 x Set screws of your selection