Mudguards. They do just that. They guard you from mud. And water and gravel and dirt and whatever else you might be riding over.
We stock Ortlieb's Quick Rack mudguards (specifically designed to work with Ortlieb Quick Racks) and a wide range of French made Zefal mudguards for the front or raer of your bike.
For the owners of Dyson Bikes Adventure Folding 20-Inch electric bike we have sets of custom made mudguards as well.