Cagoule CoolMax®

The CoolMax balaclava is well crafted, quality item. I haven't noticed it was cooler than the light cotton or silk balaclavas that I have been using up till now. But, being a synthetic material, it does not feel as soggy when moist or wet — and it's capacity to dry faster than the natural fibers balaclavas seems to bear that.
Quite frankly, I don't wear one to feel cooler inside a helmet but mainly for hygienic purpose because a balaclava is A LOT easier to wash than a helmet liner... It is quite long in the neck and can easily be tucked in your jacket — not sure you really want to do that when you're too hot though!
It is one size fit all but is on the larger size. I wear a Large size helmet and its slightly loose on me. And don't count on shrinkage from washing: for better or for worse, it doesn't (synthetic, remember?).
I want to take this opportunity to give kudos to the customer service at GEARS. One of the balaclavas I received was not the current model but an earlier version, of a different colour from the description. It was replaced without hassle or suspicious questions. I appreciate dealing with straightforward people and will not hesitate to recommend GEARS to any of my riding friends.