Most trail running socks are simply dark colored running socks with no specific "trail" features built-in. The Drymax Trail Running socks are the exception. Trail dirt inside a sock is a bad thing; it can easily cause blisters or rib the skin raw. To help prevent dirt from getting inside Drymax Trail socks, we did not include vents. In addition, the Trail socks" double welted leg has extra padding around the ankle. This extra padding protects the leg and seals the top of the shoe to keep out dirt and debris. Wet feet can be a trail runner"s worst enemy and getting wet feet is almost inevitable. The Drymax Trail Running socks" Dual Layer Moisture Elimination System actually removes sweat, sweat vapors and water from the skin through the inner Drymax layer to the outer absorbent layer. The double welt top is made of Drymax fibers to repel water, so when a runner splashes through a creek, the top of the socks stay dry. Drymax Trail Running Socks are a Medium+ Density protective padded sock. Dense padding is used, as opposed to thick padding, as it protects feet without adversely affecting the fit of the shoes. The Trail Running Socks were designed for use to be used in cool to warm conditions, keeping feet dry, comfortable and odor free all day long.