The fabric has interfacing applied, resulting in a sturdy construction. Depending on the size of the lunch box or containers you use, it can hold 1-2. If you also want to put in a water bottle, it will likely only hold one. Size: Exterior: 20cm (height) x 29cm (width) x 10cm (depth) Interior: Thermal insulation sheet (15cm), inner fabric (5cm) As this is handmade, the finished size may vary. Also, while I make them with care, there may be some imperfections such as slight distortions or minor mistakes.