Diamondback DB15 Combo 5.56x45mm NATO & 300 Blackout 16″ Two-Upper Rifle with FDE Carbon Receiver & 12″ M-LOK Handguard

Diamondback DB15 Combo Two-Upper Rifle

The Diamondback DB15 Combo (model DB1721K061) is a gas-impingement rifle that ships with two complete upper assemblies — one chambered in 5.56x45mm NATO and one chambered in .300 Blackout — allowing the shooter to switch between calibers using a single lower receiver. Both uppers feature a 16-inch 4140 chrome moly barrel.

Key Features

• Two upper assemblies included: 5.56x45mm NATO and .300 Blackout
• Gas-impingement operating system
• 16" 4140 chrome moly barrel
• A3 flat-top upper receiver in FDE carbon finish
• Carbine-length gas system
• 12" M-LOK handguard
• Magpul MOE carbine stock in black
• Magpul MOE pistol grip in black
• A2 flash hider muzzle device
• 30+1 capacity
• CNC machined components
• Made in the USA

The lower receiver pairs with either upper, and the package includes two uppers as noted in the model designation. The stock and grip are Magpul MOE components finished in black, contrasting the FDE carbon receiver.

ICB Firearms carries the Diamondback DB15 Combo and ships nationwide to your local FFL dealer. Local pickup is available at our Saint Clair Shores, Michigan location.