Most boot, shoe and sandal deodorizers mask the smelly bacterial residues in hiking, climbing and beachcombing footwear, but Granger's Odor Eliminator has a long-lasting formula that treats foot odors without perfumes or other scents. The water-based formula is safe for all fabrics and tested in Gore-Tex footwear. It comes in two sizes, although many backpackers swear by the 2-oz. portable version, especially in cramped ultralight tents where inhabitants sleep head-to-foot like sardines (sans odor).