Nikwax Aqueous Nikwax 33.8 fl. oz. Leather Waterproofing is a brush-on water-based treatment ideal for footwear that is subjected to wet and abrasive conditions. In addition to waterproofing, the application keeps boots cleaner and maintains the leathers suppleness for improved durability. Conveniently, Aqueous Wax can be applied to wet or dry boots. It may darken leather and wax down the texture of nubuck and suede leathers.