F5 Storm Shelters will not be undersold! With our F5 Storm Shelter ECONO line, we’ve built the product with your budget in mind. Our ECONO line shelters are still among the top in the industry. Engineered to withstand 250 MPH plus winds. Our shelters are completely fabricated from steel and fully coated with up to 100 year plus rust protection. F5 Storm Shelters, Inc. has engineered and tested an all steel storm shelter capable of withstanding a category EF5 tornado. An F5 Storm Shelter also has a fully integrated shelving system and up to five times more ventilation than our competitors.