Crosby Fist-Grip Clips are made from heavy-duty forged steel. They are hot-dip galvanized and meet or exceed the performance requirements of Federal Specification FF-C-450 Type III, Class 1.
New Style vs. Old Style
If you're confused about which is which, just know that sizes 5/8" and under are G-429N (the "N" stands for "New Style") and sizes 3/4" and over are G-429. The overall function is the same between these two clamps, but cosmetically they are slightly different.