AT3™ Low Profile Steel AR 15 Gas Block + Gas Tube + Roll Pin Combo

Buy As A Set And Save!

This combo includes your choice of 4 different sizes of gas blocks, your choice of 4 different gas tube lengths, and 2 roll pins.

How to purchase: Use the dropdown menus to choose your size of gas block and gas tube length. Not sure what size you need? Check out the FAQ at the bottom of this page.

About the AT3 Low Profile Steel Gas Blocks:

• 4 sizes available: .625″, .75″, .825″, and .936 (.75″ is the most common size, but always measure the barrel if you aren’t sure!)
• Low profile design, perfect with all free float handguards
• Premium steel construction (better than aluminum for withstanding extreme temperatures)
• Secured using 2 set screws (screws, Allen wrench and roll pin included)
• Backed by the AT3 Lifetime Warranty

About the AT3 Gas Tubes:

Premium stainless steel gas tubes, available in 4 lengths. Backed by a lifetime warranty.

Not sure what size you need? Measure the distance from the barrel shoulder to the gas port on your barrel and compare it to the chart below. (Carbine is the most common length).

Distance to port:

• Pistol = 4 inches
• Carbine = 7 inches
• Mid = 9 inches
• Rifle = 12 inches

More Details:

AT3 Gas Block Specifications:

• Material: 4150 Steel, Black Finish
• Length: 1″
• Height: Sits 3/8″ off of the barrel (fits under all free float handguards)
• Weight: 1.5-1.8oz depending on size

AT3 Gas Tube Specifications:

• Material: Stainless Steel
• Finish: Natural

Total Tube Length:

• Pistol: 6 3/4″
• Carbine: 9 3/4″
• Mid-length: 11 3/4″
• Rifle: 15 1/4″

Frequently asked questions:

Q: How can I tell what size of gas block I need?

A: The gas block size is based on the outside diameter of your barrel. The most common size is .75″ (this is the military standard). If you aren’t sure – use calipers to measure the diameter of the barrel, in the area where the gas block sits. Or alternatively, you can try looking up the make and model of your rifle online for more details.

Q: How do I know if this gas block will fit under my handguard?

A: Our micro gas blocks are as small as you will find on the market. They are guaranteed to work with our AT3 handguards, and they are compatible with all the other handguards out there!

The AT3 Tactical store has a 90 day no-hassle return policy for products in good condition. You can view the full details of our return policy here.

If you encounter an issue or defect with a product after 90 days of your purchase, you can refer to the manufacturer for a warranty claim. Their policies are below.

All AT3 Tactical Brand Products carry a lifetime warranty against manufacturer’s defects.

This includes AT3 Red Dot Sights, Handguards, Iron Sights, and any other product that carries the “AT3 Tactical” or “AT3™” name. For other brands (ex. Magpul or Troy), please refer to the manufacturer’s warranty policy.

In the event that your AT3™ product becomes unusable, we will repair or replace the product at no charge to you.

If we cannot repair your product, we will replace it with a product in perfect working order of equal or better physical condition. The warranty is fully transferable, but we may require information about the original purchase to validate the authenticity of the product.

If your product is in need of warranty service, please contact AT3 Tactical to start the process

Our contact info is available here. To expedite processing, please provide your order information and description of the defect.

Please note: The AT3 Lifetime Warranty does not cover loss, theft, intentional damage or cosmetic damage that doesn’t affect the performance of the product.