This is a normal pistol buffer tube not made by KAK

KAK INDUSTRIES SHOCKWAVE BLADE PISTOL STABILIZER - BLACK

Features:

Fits all pistols equipped with a standard AR-15 pistol buffer tube (up to 1.25 in diameter) AR pattern, Glock, CZ Scorpion Evo 3, HK9X pattern, etc.
Available in black and flat dark earth (this listing is for black)
Quick and easy to install
Provides additional support during firing
Weighs a scant 5.0 ounces
ATF approved for pistol use
Veteran designed, engineered, marketed, and sold
Made in U.S.A.
Manufacture Description: Shockwave is proud to introduce the patent-pending Blade pistol stabilizer. Made from high-strength glass-reinforced polymer, the Blade is manufactured to exacting tolerances and fits all pistols equipped with a standard AR-15 pistol buffer tube (up to 1.25 in diameter). No special receiver extension needed. No half-hour installation process. Just slip it on and tighten the large set screw for a rock-solid installation.

AR-15 .223/5.56 Complete PISTOL BUFFER TUBE

Includes:
        -Pistol Buffer Tube
        -Buffer
        -Buffer Spring
        -Steel End Plate
        -Steel Castle Nut

Details:
        CNC machined aluminum buffer tube to fit carbine buffer and spring.
        Hard anodized type III black finish.
        Machined lower slot to accept all end plates and sling mounting accessories.
        Superior Quality Carbine Buffer Spring
        Standard 3.0 oz buffer Quality Polyurethane Bumper for longer life
        Steel Ambidextrous End plate and Castle nut.
        Buffer tubes measure 7-5/16"

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