If you have not encountered the Tokyo Marui Non-Freon GUNPOWER as a power source for your gas blowbacks, watch this video review by テイクアールチャンネル if it is something for you to consider in the future... "This time, I tried Tokyo Marui's non-CFC power. For the time being, I thought it could be used as a room-style shooter in the summer without any problems! However, the problem is still the price... It costs more than twice as much as the 152A, so you need to pay more than twice for the one with inferior performance, so it seems that it will take some time for it to spread widely."