Left unprotected and exposed to sunlight your hot tub cover will crack and degrade over time. Instead of spending hundreds of pounds every few years replacing covers, simply treat your cover every month with 303 Protectant which will protect it from UVA and UVB and restore a brand new shiny look to your hot tub cover. 303 bonds into the vinyl surface to block the sun's UV rays and guard against cracking and fading and, with regular use, 303 will provide 100% protection against UV fading.