Nikwax says about the Twin Fabric & Leather-Footwear Cleaning Gel
Footwear Cleaning Gel: Sponge-on cleaner for all waterproof footwear. Cleans effectively, restores water repellency and revives breathability. Revives the performance of your footwear, keeping your feet warmer and drier. Recommended for Gore-Tex®, Sympatex® eVent® and all other waterproof footwear.
Fabric & Leather Proof: For waterproofing footwear. Easy to use sponge-on waterproofing for all fabric, leather and combination footwear. Adds water repellency and revives breathability without softening leather. Enhances the performance of your footwear, keeping your feet warmer and drier. Recommended for Gore-Tex® and eVent®, Sympatex ® and all other waterproof combination footwear.