Little Boys Thermal Clothing Long Johns (British Made) Viscose, Polyester, Elastic closure 1 x Thermal Long Johns Warm thermal wear. Brushed and side seam free. 50% Viscose and 50% Polyester. Inside leg: 2-3 years (13 inch), 3-5 years (16 inch), 6-8 years (18 inch), 9-11 years (22 inch), 12-13 (24 inch). Thermal Underwear Made in England