From Armalite:

"ArmaLite is known for its history of innovation. Its Special Purpose Rifle (SPR)
has proved it for years. Now, the introduction of the ArmaLite SPR Mod 1 proves
it once more, in spectacular fashion. The SPR Mod 1 is forged, one-piece upper
receiver/rail system with exclusive detachable side and bottom rails.

In true ArmaLite fashion, the SPR Mod 1 is like no other on the market. With other one-piece systems, you're stuck forever with the rails you get at purchase, and stuck with their limits.

But ArmaLite knows you and your firearm often have more than one mission, and you want options. ArmaLite gives you just that. The SPR Mod 1's three o'clock, six o'clock, and nine o'clock rails are detachable. That's right, you can change your 1913 rails to fit your changing needs for sights... lights...lasers...grips...or swivels.

ArmaLite takes that versatility even further. Each SPR Mod 1 comes with three extra rails standard, at no extra cost. We give you a 1913 rail with quick detchable sling swivel hole. Each rifle comes with a low insert for when you need a bare rail with a low profile. There's also a plain insert with a quick detach sling swivel hole. Changing your rails...your add-ons...and your SPR Mod 1... is as easy as turning a torque wrench.

Ingenious versatility isn't the only reason you'll want an SPR Mod 1. Its one-piece construction offers you a continuous optic platform (COP). There's no gap to bridge between receiver and upper rail when you're installing your scope or sights. This one-piece construction also gives the sighting platform extra rigidity. It's a good, strong backbone. That means your sights will stay zeroed in the most trying conditions.

The SPR Mod 1 typifies the "ArmaLite Standard of Excellence." With us, quality comes standard. There's no extra charge for: the SPR Mod 1's chrome lined, chrome moly vanadium steel barrel; its two-stage tactical trigger; the patented, extra strength steel bolt assembly; or the hard coated finish. These are all things that the other companies consider options at an added cost.

The introduction of the new ArmaLite SPR Mod 1 is truly a new chapter in our history of innovation and our dedication to the quality you deserve."

• Caliber: .223/5.56 X 45 mm NATO
• Barrel: Free Floated 16" Double Lapped, Chrome Lined\Chrome Moly Vanadium MIL-B-11595-E, Threaded 1/2x28
• Rifling Twist: RH 1:7" 69 - 80 Ammo Grain
• Muzzle Device: Flash Suppressor
• Front Sight Base: Gas Block with Picatinny Rail Top of gas block is .293 (+/-) lower than top of upper receiver
• Upper Receiver: Forged Flattop with Picatinny Rail & Laser Engraved Rail Numbering, 7075-T6 Aluminum w/ 8" Hand-guard
• Lower Receiver: 7075-T6 Aluminum (forged)
• Trigger: Tactical Two Stage, 1st Stage 3.5 lbs - 2nd Stage Approximately 5-6 lbs
• Overall Length: 35.5" with stock extended, Approximately 32" collapsed
• Weight: Approximately 6.5 lbs
• Finish: Anodized Aluminum Upper/Lower Receiver, Manganese Phosphated Steel Barrel
• Accuracy: 1.5 - 2.5 MOA
• Included with Rifle: One 30 Round Magazine, Sling, Black Case, Owner's Manual, Limited Lifetime Warranty