Simple logic tells us that when the weather is warm, the sun is shining. And while the need to protect your skin rises in this scenario, we all know that long sleeves and arm warmers typically fall under the 'absurd' category when it's hot out. For this reason, Outdoor Research created the Sentinel Sun Sleeves. These sleeves were developed for warm weather, so the thought of overheating should be immediately dispelled. Instead, you gain cooling comfort against the sun's damaging rays. How' Well, Outdoor Research constructed the Sentinel sleeves from UV resistant fabrics with a minimum protection level of UPF 50. Additionally, these same fabrics have been designated as a Solar Shield product, meaning that you gain a SPF 30 level of protection, as well. Just as importantly, the Sentinel's fabric has been treated with Insect Shield Permethrin insect repellent. Essentially, this is an EPA registered repellent that nearly eliminates the risk of bites, and their potential diseases, from mosquitoes, ticks, ants, flies, and chiggers. Even better, this repellent is odorless, and it won't intensify from perspiration. In terms of fit, the sleeves are able to be worn to the knuckle, and a thumb hole has been sewn into the hand section. At the top of the sleeve, Outdoor Research secured the next to skin fit with a silicone gripper. The Outdoor Research Sentinel Sun Sleeves are available in the color Alloy and in the sizes SmallMedium and LargeX Large.