KWC .50 Desert Eagle Style CO2 Airsoft gun BK EXTREMA RATIO – Enlarged aluminum magazine well – Enlarged aluminum magazine well enabling seamless reloads– Ambidextrous safety levers works with all shooters– High vis green fiber optic front sight matching the real pistol– Utilizes CO2 magazines– This is a dual system pistol which can use CO2 mag (400fps) and also can use Green Gas mags (330fps) the internal firing valve is balanced and the only force applied during firing is the main spring Metal upper with polymer frame The rail top is indeed 20mm but the curved beveling around the edges means that it will not necessarily fit all rail attach type optics so it will take a little trial and error without the right interface adapter