Square tin with rounded corners and hinged lid, the lid is painted brown with green lettering reading 'STERILIZING OUTFIT FOR USE WITH WATER BOTTLES - KEEP DRY', the inside of the tin lid is inscribed instructions for use, inside the tin are two bottles - one of brown glass and one clear, the brown glass bottle is labelled '50 THIO TABLETS' and the clear bottle is labelled '50 STERILISING TABLETS'.