Product Description The Yankee Hill Machine Co caliber-marked dust cover assembly is designed for AR-style upper receivers and is ideal for builders who may swap uppers or calibers and want clear identification at a glance. This complete assembly includes a 5.56 NATO caliber-marked ejection port cover along with the required rod, retaining clip, and spring for installation. Product Highlights Caliber-marked ejection port dust cover helps identify 5.56 NATO uppers quickly Complete dust cover assembly for AR-style rifles Includes rod, retaining clip, and spring for a ready-to-install kit Great upgrade or replacement part for new builds and maintenance Made by Yankee Hill Machine Co for reliable fit and function Specs Brand: Yankee Hill Machine Co Product Type: Ejection port dust cover assembly Caliber Marking: 5.56 NATO Compatibility: AR-style rifles (upper receiver ejection port cover) Included Components: Caliber-marked dust cover, rod, retaining clip, spring Manufacturer Part Number: YHM-111-556 UPC: 816701017687 Disclaimer: We strive to provide accurate and up-to-date product descriptions, specifications, and images; however, errors or omissions may occasionally occur. We are not responsible for any inaccuracies or discrepancies in the content provided. If you notice anything incorrect or unclear, please contact us so we can correct it. When in doubt, we recommend verifying details directly with the product&';s manufacturer.