SW Medium Weight Hiking Socks are my go-to winter sock - not just for hiking! So snuggly warm, and cushiony to bear all the shocks of the daily run around. I wear them with my Teva sandals in all seasons and my feet stay toasty. My 8.5 size middle-aged feet feel just right in a Medium. The socks do shrink a bit initially when washed in warm water and dried in the dryer at medium heat, but they fit even better then, and get softer with age and washings (I put a half cup of white distilled vinegar in the washer softener cycle). I have other pairs that owned for almost a decade, and they are wearing like iron. I only hike in them in the coldest weather, because they are so warm, but also a bit squishy which makes my feet move around in my boots a little more than I like. My only real complaint is about the Woodrose color. It's lighter than shown on GoBros.com and what I like to wear in socks. I can't say enough about GoBros!!! I found them through Amazon during a search for these particular socks. They won my heart over with a great web site, pain-free ordering with Amazon Store Card or PayPal, excellent customer service and fast delivery. The prices seem slightly high, but with price match, Smartwool 20% off sale and free shipping/no minimum, I didn't mind. Calling customer service was a pleasant and productive experience. My feet thank you GoBros, I know they'll be back for more!