BYRNA SD UNIVERSAL KIT - BLACK. The Byrna SD (Self Defense) is the successor of the Byrna HD. It has been re-engineered for optimal performance. Powered by compressed air (CO2), the Byrna SD shoots .68 caliber round kinetic and/or chemical irritant projectiles that can disable a threat from up to 50-feet away. It is an incredibly powerful and non-lethal self-defense weapon. Includes: 15 .68 caliber projectiles, two 5-round magazines, and two 8-gram CO2 cartridges Features a Picatinny rail for accessory mounting Honeycomb over-molded grip ensures better control Ambidextrous safe/fire switch for both left- and right-handed users Enhanced sights allow faster target acquisition Straight trigger with a 6-8 lb. pull weight Patented Pull-Pierce Technology: CO2 remains unpunctured until the first trigger pull, puncturing the CO2 and launching the projectile simultaneously Standoff Distance: Accurate up to 60 feet.