It's lightweight, long wearing and rigid.
WARNING: When using screeds always avoid contact with electrical power lines or any electrical source. Marshalltown's ##4735 1-1/2#" X 3 1/2#" X 16' Magnesium Screed is made from magnesium alloy, which won't rust or rot. The end is capped to prevent concrete from getting inside. Marshalltown 1-1/2IN X 3 1/2IN X 16FT Magnesium Screed - By International Tool.