 They have a white double coat which requires regular brushing with a wire comb in order to prevent matting . It has a dense undercoat , while the outer coat is wiry and weather resistant . Markings on the face can be in a variety of colours including lemon , black , brown , blue , and badger , which is a mix of brown and black . Heavy body markings or patches or excessive ticking on the coat are discouraged . Sealyhams are low to the ground , and in muddy weather their long coats can become quite dirty . Sealyham coats are groomed by hand stripping , in order to keep the coat from becoming too soft . 
