The Glock G20 Gen5 MOS is a full-size 10mm Auto striker-fired pistol with a 4.61-inch barrel, 15+1 capacity, and 29.81 oz weight. The MOS (Modular Optics System) cut on the slide supports direct mounting of common red dot sights without a separate adapter. Finish is Black nDLC (Nitride). The polymer frame includes interchangeable backstraps. 
 

Key Specifications 

• Brand: Glock 
• Model: G20 Gen5 MOS 
• UPC: 764503059889 
• Action Type: Semi-Automatic (Safe Action) 
• Caliber: 10mm Auto 
• Barrel Length: 4.61 inches 
• Capacity: 15+1 rounds 
• Weight: 29.81 oz 
• Finish: Black nDLC 
• Sights: Fixed Glock Sights 
   

Detailed Features 

 
The MOS cut gives you a standardized optics interface so you can mount a red dot without extra machining. The nDLC slide finish resists corrosion and wear. Interchangeable backstraps let you adjust grip circumference for hand size. The Safe Action trigger system integrates a firing pin safety and trigger block, with no external manual safety. At 29.81 oz unloaded, the G20 is noticeably heavier than a 9mm Glock of the same size, which is partly absorbed by the 10mm recoil.

The G20 Gen5 MOS draws a consistent crowd: 10mm fans who want a Glock platform, hunters looking for a sidearm, and shooters who want the MOS optics capability on a high-power pistol.

10mm performance gets the most discussion. The caliber is valued for its stopping power in hunting and self-defense contexts, and the G20 is one of the primary platforms for it.

Reliability is rarely questioned. Glock's reputation carries through, and G20 owners report problem-free operation.

The recurring criticisms: grip size feels large to some shooters with smaller hands, and the 10mm recoil is noticeable, manageable for most owners but acknowledged as more than what they'd get from a 9mm. Neither of these is unique to the MOS version.