it is also important to select the thicknesses of these components in order to provide a folding umbrella that is both light weight and compact while providing the necessary structural strength and flexibility to prevent forces such as wind which invert the open umbrella from subjecting the umbrella frame from experiencing permanent distortion and damage the materials typically employed in folding umbrellas and their advantages and disadvantages are aluminum although aluminum is a light weight metal and is capable of producing inexpensive frame components an all aluminum rib has the disadvantage of being easily distorted when subjected to bending and not return to is original shape when the force causing bending is removed thereby causing permanent damage to all aluminum components steel like aluminum an all steel rib will remain distorted after the umbrella inverts since steel will remain distorted if the rib is bent due to wind force steel has the disadvantage of being significantly heavier than aluminum and is less resistant to corrosion than aluminum plastic all plastic ribs offer some flexibility but lack the strength of metal alloys all plastic ribs or partial plastic ribs are more likely to break or snap when stressed by wind force carbon fiber carbon fiber is made of thin strands of carbon while fiberglass is made of.