Platform boots Princess Polly Lower Impact Upper, lining & insole: 100% water-based PU Outsole: 100% rubber Faux matte leather material Zip fastening at side Block heel Rounded toe Padded insole Heel height 13.5cm / 5.3in Platform height: 5cm / 1.9in Water-based PU is manufactured using an alternative to chemical solvents which is entirely water-based. This is not only better for the planet, but is better for our workers.