B1/2-20 x 4 1/2 MS90727, Alloy Steel B1821 Fine Cap Screw Per ASTM A354BD Zinc Yellow DFAR MSRB The external sems feature allows

The external sems feature allows the screw to be used with a nut or washer

The 5/8-11 thread size means that the nut can be used with bolts and screws that have a 5/8-11 thread pitch

The full thread design provides maximum holding strength throughout the screw's length

The washer has a split design that allows it to conform to the shape of the materials being fastened

These 10-16 x 3/4" Unslotted Indent Hex Washer Self Drill Screws are made of durable 316 stainless steel

B1/2-20 x 4 1/2 MS90727, Alloy Steel B1821 Fine Cap Screw Per ASTM A354BD Zinc Yellow DFAR MSRB The external sems feature allowsB1 2 20 x 4 1 2 MS90727 is an Alloy Steel B1821 Fine Cap Screw manufactured according to ASTM A354BD standards. It has a nominal diameter of 1 2 inch, a thread pitch of 20 threads per inch, and a length of 4 1 2 inches. The screw is zinc plated yellow and meets DFAR requirements. It is typically used in high strength applications where vibration resistance is critical.