Galvanized steel gutters are one of the strongest of all the metals that are commonly used for gutter systems. Galvanized gutters are steel gutters that are immersed in molten zinc and it's the zinc coating that protects the gutter against the elements and rusting out over time. Galvanized steel gutters will hold up in extreme cold and hot temperatures and are particularly popular in areas with snow and ice. They can be soldered at the joints or pop riveted and sealed with a seam sealer.
Galvanized gutters, particularly the zinc coating on the gutter, should hold up for decades before there are any signs of corrosion. They are available in 10' and 20' lengths in both K Style and Half Round Galvanized Rain Gutter profiles.