Presma Pistol Buffer Tube Kit w/Pistol Buffer Tube Black. 3 in pistol buffer tube recoil buffer buffer spring receiver end plate and castle nut. Specifications for Presma Pistol Buffer Tube Kit w/Pistol Buffer Tube: Manufacturer: Presma Color: Black Gun Make: AR Platform Included Accessories: Pistol Buffer Tube Package Contents: Presma Pistol Buffer Tube Kit w/Pistol Buffer Tube Presma UB-AS5P05: Pistol Buffer Tube Kit w/Pistol Buffer Tube Black