The Diamondback DB9 G4 is a DAO 9mm subcompact pistol with a 3.1-inch barrel, 6+1 capacity, nickel boron stainless slide, and mint green polymer frame. It's one of the more compact and lightweight 9mm pistols available at 0.8 lbs unloaded. 
 

Key Specifications 

• Brand: Diamondback 
• Model Name: DB9 G4 
• Caliber: 9MM Luger (9x19 Para) 
• Action: Double Action Only (DAO) 
• Capacity: 6+1 rounds 
• Barrel Length: 3.1 inches 
• Overall Length: 10.9 inches 
• Weight: 0.8 lbs 
• Sights: 3-Dot 
• Grip Material: Mint Polymer 
• Safety Feature: Firing Pin safety 
• Finish Color: Mint Green / Nickel Boron Stainless Slide 
   

Detailed Features 

 
At 0.8 lbs the DB9 G4 is notably light for a 9mm, which is its main selling point for carry. The DAO trigger gives a consistent pull on every shot with no external hammer to manage. The firing pin safety is passive. The 6+1 capacity is on the lower end for a 9mm but is a direct result of the very small frame dimensions. Three-dot sights are standard. The nickel boron stainless slide finish resists corrosion.

The DB9 G4 is bought almost exclusively for its size and weight. At 0.8 lbs it's one of the lightest 9mm pistols made, and owners who carry it choose it specifically for deep concealment or backup carry where a heavier gun isn't practical.

The compact size comes with real tradeoffs that owners discuss frankly. At 0.8 lbs, recoil with standard 9mm loads is sharp and follow-up shots take more effort to manage. Some owners report reliability issues. Failures to feed and failures to eject occur more frequently than with heavier, larger-framed pistols, particularly with hollow point ammunition. Ammo sensitivity is a recurring theme.

The price is a positive, and Diamondback's customer service gets mixed reviews when warranty issues arise. Owners who understand the DB9's purpose, extremely lightweight backup carry, are generally satisfied; those who bought it expecting the reliability of a full-size pistol tend to be disappointed.