Hiking into the river can be an ordeal on warm days, so ditch the waders in favor of the Korkers I-Drain 3. 5mm Neoprene Guard Sock. This abrasion-resistant sock features a gravel guard to keep debris out of your boot both while you're hiking and while you're wading. The 3. 5mm thickness maintains the same fit inside your boot while the neoprene stretches to conform to your foot's unique shape. Underfoot, perforated Airprene material allows water and perspiration to drain-preventing your foot from feeling swampy.