If you want a tight fit this hat may be for you. My head is 22.5 inches and I found this one to be too tight. Had to send it back. Smartwool makes great products....I wish they offered this hat in sizes other than one size fits all....cause it don't, peoples.

Great for active sports in temps down into freezing without wind. I have also used as a helmet liner as it is more comfortable than the one supplied with the Bern Baker. Otherwise great for cool climates without much activity, but it is a little "snug"

Smartwool Beanie is made from fine merino wool, its super comfortable, doesn't itch, plus perfect for all conditions warm or cold. I have a couple of the SmartWool Beanie's I use in the fall and winter for training runs then I toss this in my pack when I'm up in the mountains in summer. Another nice thing is its machine washable. Additional note product does run small.

This beanie has a near perfect fit on my head. It's so light that it doesn't weigh my head down. And the elasticity is just right. Clean lines and great colors. This is a great choice.

I love my SmartWool training beanie. It keeps me warm, yet wicks the sweat so I don't overheat. It also doesn't ride up when I'm running -- something I've experienced before with other hats.

Looks like a simple beanie, but once you put it to work, it does not disappoint. The logo is always a nice touch with Smartwool product. Very comfortable fit.

It is warm and thin and doesnt slide...and I really like it...but it is wool and therefore itchy. I wish it had a liner along the edge so that my forehead would not be so bothered by it.

Think jersey weight, 2 layers. This is my cold weather hiking hat. Covers the ears and just enough noggin. It is my first layer on when the temps start dropping and my first line of defense against overheating. Small and light. Great sleeping cap too.

I wear this beanie whenever I hit the trails. Stays in place and I don't have to keep pulling it down over my ears. It's thin but warm. I want another.

Super soft and lightweight. Not itchy at all and fits under my bicycle helmet for cold weather riding.

You will not be disappointed.

I have 2 of these awesome caps. Rain, snow or shine....I wear this cap all the time. It is a little tight but great if you are wearing a helmet or need a light lid from a cold weather jog. Highly recommend it!

I was looking for a lightweight hat for XC skiing and this fits the bill without being too pricey. It breathes well yet blocks more wind than a fleece hat. Covers my ears and even fits under a bike helmet. Easy to stuff in a pocket.

This was exactly what I was looking for. I have acrylic beanies galore, but they aren't warm enough in very cold conditions. Got fleece ones, but head end up suffocating because there is no airflow. I decide to look on Backcountry for a good wool beanie. Saw this one on sale, read other reviews and decided to give it a go. Its perfect, just what I wanted. Its a snug fit, but not tight to be uncomfortable. Its very warm, yet the air flows so head doesn't sweat. I love it. Good for casual wear, and great for exercising outdoors in winter. In more extreme cold conditions could probably do with a shell

I didn't really like this. It fit like a swim cap; just too tight for my liking. I prefer my Ibex cap.
I sent it back.

This is my second smartwool beanie. my first one is a little lighter so i'm not sure if it's a different model or what, but I love both of them and want two more! i wash them by hand in dr. bronner's pepperment and then let them dry right on my head. they still keep me warm. buy this hat!

Just the right amount of warmth for running in 20-40 degree fall/winter temperatures. On the plus side it is light weight, odor resistant, durable and itch free. It still has room for improvement to include offering sizing options and incorporation of reflective material for night time outings. All around it is a great head cover for the active outdoor enthusiast.

The hat fits quite snug and I wear a 7 1/8" baseball hat. It is very light weight and thin, so it could easily be worn under a helmet. I had trouble keeping it down completely over my ears (ref relatively small/med head size above), which left me a bit cold skiing in 20deg weather in Ohio (humid and cold). On the warmer days it performs very well and is very comfortable. It stays dry and is not itchy in the slightest. Good price for the high quality wool you get.