1" I60 stainless grating clips are designed for use on fiberglass, pultruded gratings that are 1" in height, while 1 1/2" I60 stainless grating clips are for use on gratings that are 1 1/2" in height or more. The 1 1/2" I60 can also be used on 1 1/2" square mesh fiberglass gratings. I60 grating clips are resistant to corrosion in most environments, due to 316SS stainless steel construction.