The #TANDEMIZED Tactical Pistol features a wide range of upgrades from TANDEMKROSS and industry partners, including: Ruger Mark IV 22/45 Tactical Upper. #TANDEMIZED Cthulhu Lower. Shadow Mount V3.0. Swampfox Optics Justice 1x27 Red Dot Sight. Inforce WILD1 Light. halo Charging Ring and TandemKase Pistol Bag.