Stay cosy with these cotton-blend thermal long johns. Regular fit, offering a medium level of warmth. Made from an insulating brushed-back cotton blend that's breathable for extra comfort. Finished with ultra-soft seams for snugness. Our clever Heatgen™ technology uses an innovative fibre blend, helping your body to generate and retain heat so you can stay warm when the weather gets chilly. We only ever use responsibly sourced cotton for our clothes.