Ultimate DirectionFk Gaiter, Color: Black, Size: Small (80603818BK-SM)

Let me start by saying I've never used gaiters before. With that said, I put in my fair share of research before purchasing the UD FT gaiters. As with most items, it's hard to get a feel for sizing and effectiveness. For reference, I run in Altra Lone Peak 4 trail shoes in size 12.5 and I'm 6'2 at 192lbs. I don't have massive calves or big ankles. Based on the sizing chart, I should be a large. Wound up buying both medium and large. When received, I tried on the large first, and they fit very well, almost tight. So I would say stick with the sizing chart unless you have string bean legs. The velcro is strong and I really like the snap as an extra fastener to help the velcro stay closed. The material used seems to be of good quality and somewhat thick but not like neoprene. I don't foresee these gaiters causing sweat accumulation like neoprene would. The strap that goes under the shoe seems sturdy yet thin and fits between the lugs of my shoes without much interference.I haven't trail tested these yet, but so far I am happy with initial impressions, quality, and fit.

The sizing of these gaiters goes by shoe size but they really should be going by ankle circumference. I got the small as I wear a women's size 7 shoe. The ankle circumference on the gaiters is 21cm/8 inches. When you take into account the overlap of the velcro that reduces the available circumference to around 15cm/ 6 inches. I have pretty small ankles and they would not fit these gaiters as you can see in the photo. I don't think I've put them on incorrectly. So be warned for those thinking of purchasing a small.

Overall great at what gaiters need to do which is block moisture and debris. The Cordura tends to grab burs and underbrush, but has held up through various midwest woodland hikes. I was hoping to attach these over my Salomon Outbacks as they are made of Cordura as well, but as I stated in the title, these are just too snug for boots. At most I was able to wear midweight merino socks, my Cascadia 15s, a merino baselayer, and tech hiking pants. This created a very tight fit with the velcro at it's widest attachment point. The most comfortable fit with no pull on my waistband or midfoot was with low top trail runners and lightweight joggers or sans the joggers with some high socks.If they made a bit larger size this would be my favorite lightweight gaiter.

These are great gaiters! Worn them on several hikes, trail runs and tough long distance races with different terrain and have had no issues. Have also worn with different trail running shoes (Altras, Saucony, Merrell and New Balance) and they fit all of them well with no adjustments needed when switching shoes. Other than the sand and dirt that’s naturally gonna get in from other parts of the shoe, these keep the big bits from getting in from your ankle. These haven’t failed me yet. The strap has lasted on several rocky river beds, large rocks, hard dirt, sand and repeated abuse on everything else. Just be sure the strap goes securely in between the row of lugs and not on top. The Velcro, button and loop that keeps it on the shoe are also solid. Best part is the style because it can be put on after you’ve put your shoe on unlike the popular style gaiters. On more than one occasion I had put on my shoe and laced up only to realize that I hadn’t slipped my gaiters on first and had to take my shoe off and start all over. These have come to my rescue. They are also super comfortable and the material and fit seems to help my feet feel more stable and makes the shoe feel more fitted and customized to my feet which I like. I have no negatives and are happy with these as my one and only forever gaiters. I wear a woman’s shoe size 8.

Update (+ photos)After adding grosgrain ribbon darts to expand the ankles 1/4" and velcro in the heel area, I tried these on an on/off-trail backpacking trip in the Sierra. When I put them on to hit the trail, I realized the left one was completely missing a snap and was significantly larger than the right one around the bottom of the gaiters (an area I had not modified). At the edge the left one one is ~1" larger (see photo). There was no hole for the snap, meaning one was never installed. I also noticed after 2 days of use that the velcro on both gaiters was coming detached due to fraying and being stitched too close to the unfinished edge.Since I was using these with trail runners, not boots I also found that the rubber straps tended to move under my heel and became slippery when wet. I ended up removing them mid-hike since the glacier scoured granite was slick enough as is. On the upside, the Cordura fabric held up well over the glaciers, talus and rocky trails.Looks like another round of mods are in store to fix the quality issues, which is disappointing for a $50 pair of gaiters.----------I do a lot of off-trail hiking/running/backpacking and tend to shred typical spandex running shoe gaiters after ~50 miles. Even though my ankles aren't thick, I upsized to a medium since a number of people mentioned that the ankle fit ran small. While the ankle wraps fit OK, the part that fits over the running shoe is baggy and there's no way it will keep out sand, snow, dirt, rocks, etc. I am not using low profile running shoes, but they are slimmer than something like a Hoka.I plan to keep them b/c of the more durable fabric, but to make them work for my shoes I will need to add darts. I am also skeptical that the under shoe strap will hold up on sandstone/granite over the longer term, but that's fixable with velcro on the heel and potentially another shoe lace hook.