The Glock G21 V MOS is a full-size semi-automatic pistol chambered in .45 ACP with a 4.61-inch barrel. It has an nDLC finish, fixed sights, and an optics-ready MOS cut on the slide. It ships with three 10-round magazines. 
 

Key Specifications 

• Brand: Glock 
• Model: G21 V MOS 
• Caliber: .45 ACP 
• Action: Semi Auto 
• Barrel Length: 4.61" 
• Capacity: 10rd 
• Color/Finish: Black / nDLC 
   

Detailed Features 

• 4.61-inch barrel with nDLC finish 
• MOS optics-ready slide cut 
• Fixed sights 
• Full-size frame 
• Ships with 3 magazines (10-round capacity each)

Owners of the G21 V MOS point to the MOS cut as the key differentiator over previous G21 generations. Mounting a red dot on a full-size .45 ACP platform without milling is a draw for those who want a duty-capable optics-ready setup without custom work.

The G21 frame draws the usual large-grip commentary. Shooters with larger hands call it comfortable and naturally filling; those with medium or smaller hands note the grip width requires adjustment. The Safe Action trigger is familiar and predictable, which most view as a strength for a service-style pistol.

The 10-round magazine limit in the V configuration is a sticking point for buyers used to higher-capacity options. Those buying for jurisdictions with magazine restrictions see this as a non-issue, while others consider it a meaningful trade-off against the platform's otherwise strong track record for reliability.