Firearms Accessories Byrna The Byrna SD Kinetic Kit comes in a protective, zippered carrying case with everything you need to get started: One (1) Byrna SDXL Launcher, Two (2) 5-Round Magazines, Two (2) Byrna 8-Gram CO2 Cartridges, (1) #byrnanation Medallion. The Byrna SD XL (Self Defense) is the successor of the Byrna HD. It has been re-engineered for optimal performance. Powered by compressed air (12g CO2), the Byrna SD XL shoots .68 caliber round kinetic and/or chemical irritant projectiles that can disable a threat from up to 60-feet away. It is an incredibly powerful and non-lethal self-defense weapon.