Standard construction site hard hat turned climbing helmet.
I measured my head circumference, it fell within the range of this helmet at about 22.5-23.0 inches. The first issue is the headband adjusts awkwardly, though it's not much of an issue and seems adequately durable. Second issue is the helmet feels small even though my measurements are within range. Third, the foam pad on top of the helmet to protect your dome from rubbing is inadequate. I shave my head though, and it rubs on top and is really annoying, which brings me too... Fourth, I don't think I'd be able to wear even the thinnest barrier/hat/balaclava underneath this helmet due to it's being small. All things considered, pretty basic basic helmet. If you have a smaller head for the measurement range, have hair, and don't plan on wearing anything bulky underneath it, it will probably be a good helmet for you.