Product DescriptionThe Glock 21 Gen5 MOS rebuilt pistol is a full-size, striker-fired .45 ACP handgun designed for dependable performance, manageable recoil, and modern optics compatibility. Built on Glock&';s Gen5 platform, this model features the Glock Marksman Barrel for improved accuracy, an optics-ready MOS slide for mounting popular miniature red dot sights with compatible adapter plates sold separately, and an ambidextrous slide stop for enhanced left- or right-hand operation. Additional Gen5 upgrades include the removal of finger grooves, a flared magwell for smoother reloads, interchangeable backstraps with beavertail options, and Glock&';s Safe Action System for consistent trigger operation and integrated safety features.Product Highlights Gen5 MOS configuration with a precision-machined optics-ready slide for red dot sight mounting Glock Marksman Barrel with enhanced polygonal rifling, target-style crown, and tighter chamber specifications Full-size polymer frame with Picatinny rail and interchangeable backstraps for adaptable ergonomics Ambidextrous slide stop levers and finger-groove-free grip profile for improved handling Rebuilt Glock 21 platform chambered in .45 ACP with black nDLC steel slide and fixed sights Specs Brand Name: Glock Model: G21 Series: Gen5 MOS Condition: Rebuilt Product Type: Semi-automatic pistol Caliber: .45 ACP Action: Striker fired Barrel Length: 4.61 in Barrel Description: Glock Marksman Barrel (GMB) Barrel Material: Steel Barrel Finish: Black Overall Length: 8.07 in Height: 5.51 in Width: 1.38 in Weight: 38.62 oz Frame Material: Polymer Frame Description: Polymer frame with Picatinny rail Frame Finish: Black Frame Size: Standard Slide Material: Steel Slide Finish: Black nDLC Slide Description: Serrated Grips: Interchangeable backstrap Hand: Ambidextrous Sights: Fixed Safety: Firing pin/trigger block Country of Manufacture: USA UPC: 764503069932 Manufacturer Part Number: G21513MOSUS 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.