WATERPROOFING. Nikwax Leather treatments waterproof with flexible long-lasting polymers and condition with tanning agents without over-softening or changing the fit, support or breathability of footwear.Waterproofing Wax for Leather – For smooth leather. A durable, soft paste wax that cures to a tough flexible, long-lasting waterproof film. Apply to dry footwear only.Long-lasting waterproofing that conditions without softening. Paste wax that liquefies at body temperature – no other heat necessary. Cures to a non-sticky durable waterproof film. Keeps waterproof leather at its optimum performance level. Available in 4.1 oz. tube, and .33 oz. sample packet.