These thermal tights from M&S come as a pack of two, built to add warmth to the coldest school runs and winter afternoons. Heatgen technology works to trap body heat, while a soft stretch welt sits comfortably at the waist without digging in. An anti bacterial treatment helps keep them fresh between washes, and the added stretch means they move easily with busy days of play. Rated for medium warmth, they layer well under skirts and dresses once the temperature drops.