I've reviewed a few, including this one at £11.99: https://www.amazon.co.uk/Xpassion-Waterproof-Anti-UV-Bicycle-Mountain/dp/B01FUAE1B8/ref=cm_cr_arp_d_product_top?ie=UTF8
They're all very similar, protect from sun and rain, quick and easy to fit and fold down into a small package. Quite useful!