I've only just applied this to my boots, so I cannot say how effective its proofing will be. However, I was stuck by how thin the solution is. I'm used to silicone-based spays that stay where they land, whereas this is very runny. Hence much of the solution ran straight off the boot and onto the floor. The bottle claims that this is environmentally friendly so - assuming it proves effective as a proofing agent - then I'm happy to get used to a different method of application.