4-Tier Insulated Tiffin with Thermally Insulated Bag Insulated 4-Tier Tiffin (tiffin has double wall) and an Insulated bag with thermal material insulation. Each Tiffin tier is watertight and has its own lid to keep liquid safe inside. The Tiffins comes with its own insulated bag, which will help keep food warm for even longer. Comes with a free stainless steel spoon.