Brits' foul-weather gear is a term used to refer to the waterproof clothing worn by people in the United Kingdom during wet and cold weather. The term is derived from the acronym MACS, which stands for 'Must-Have All-Weather Clothing System'. This system was developed by the British Ministry of Defence in the late 1980s and consists of a jacket, trousers, and hat made from a waterproof fabric. The clothing is designed to keep the wearer warm and dry in all types of weather conditions.