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AR-15 MK4 Receiver Extension Kit
AR-15 MK4 Receiver Extension Kit
AR-15 MK4 Receiver Extension Kit
AR-15 MK4 Receiver Extension Kit
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CMMG - AR-15 MK4 Receiver Extension Kit

1 Review
AR-15 MK4 Receiver Extension Kit
Brownells #
100037932
MFR #
55CA9D7
UPC
816422020676
$38.08
Coupon Code
Purchase Limit Help

In stock

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Standard Shipping Estimated Delivery
Estimated delivery: Sep 25
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Specifications
Material:
Aluminum
Color:
Matte Black
Buffer Tube Type:
Mil-Spec
Buttstock Fit:
Carbine
Make Model Fit:
AR-15.Universal;AR-308.Universal
Quantity:
1
Restriction
Gun Part Restrictions:
Yes
Prop 65 restriction:
Warning! Cancer and Reproductive Harm. Www.p65warnings.ca.gov
View US State Restrictions
Can we ship this to you? (US only)
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How To Buy Guns Online

International purchase information

What is the CMMG - AR-15 MK4 Receiver Extension Kit?
Mil-Spec 6-position adjustable Carbine Receiver Extension (buffer tube). Made from aluminum with a matte black hard coat anodized finish, accepts mil-spec pattern carbine length buttstocks or pistol braces.

See all of our AR15s and AR15 parts here.

Gun Part Restriction
Gun Parts have restricted shipping to CA.

Prop 65WARNING: Cancer & Reproductive Harm - www.P65Warnings.ca.gov

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AR-15 RECEIVER EXTENSION REVIEWS

5.0
1 Review
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5
Good buy
Quality product
by CAMILLO P. on June 28, 2026
Verified Purchase
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