EXI was another knock off brand of Align. They were sold through Xheli for a while. Now, anyone with them are SOL and must purchase somewhere else because Xheli no longer sells them. Hell, I can't find them anywhere anymore. But, like HK, and the other clones, they are compatible with Align. I had one and it fought me so friggin hard that I had to make that decal. Now, MadRat owns it from here on the forum, and he never flies it. I even tried buying it back, and he won't sell it lmao.