Product DescriptionThe Primary Weapons MK114 Mod 1-M Upper is a premium AR-15 complete upper receiver assembly built for shooters who want reliable piston-driven performance in a versatile 223 Wylde platform. It features a 14.5-inch 416R steel barrel with an anodized finish, a 1:8 twist rate, and a black M-LOK handguard for modern accessory compatibility. Designed with Primary Weapons&'; long-stroke piston system and an adjustable gas system, this upper is engineered to deliver dependable cycling, cleaner operation, and excellent adaptability across a range of shooting applications. This configuration is supplied without a muzzle device.Product Highlights Complete MK114 Mod 1-M upper receiver assembly for AR-15 platforms chambered in 223 Wylde. 14.5-inch 416R steel barrel with anodized finish for durability and accuracy-focused performance. Long-stroke piston operating system helps promote reliable function and reduced fouling in the action. Adjustable gas system allows users to fine-tune operation for different ammunition and shooting setups. Black M-LOK handguard provides a streamlined profile with flexible mounting options for accessories. Specs Product Type: Upper Receiver Assembly Model: MK114 Mod 1-M Platform Fit: AR-15 Caliber: 223 Wylde Barrel Length: 14.5 in Barrel Material: 416R Steel Barrel Finish: Anodized Twist Rate: 1:8 Operating System: Long-Stroke Piston Gas System: Adjustable Handguard: M-LOK Muzzle Device: None Color: Black UPC: 811154033482 Manufacturer Part Number: MK1M1U22314NC Brand Name: Primary Weapons 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.