I didnt think there was any real difference, but the cool fuel was labled for helis. Ive been using SIG Champion Fuel with 15% nitro and 20% lube while it was cold but I got 10% nitro this time since its getting warmer out. I still woder about the cool fule though , its green . Guess im just used to the pink stuff. Now if the canadians will just stop sending down those artic jet streams.