Strong vinyl pouch with hook and loop Velcro® closure.Caution: These bags were not designed or intended for submerged use.They are intended to keep gear dry in conditions such as rain, heavy dews, spray or splashing.Properly closed it will also keep water out in a quick immersion.Do not store electrical, photographic, or optical equipment in these bags as damage to these types of items could result.Small: 12.5cm x 18cmMedium: 18cm x 25cmLarge: 27cm x 34cm