E-Track is 7/16" high, or .4375"
1/2" plywood is 15/32 (or .46875" - a difference of .03125, or 1/32")
3/4" plywood is 23/32 (or .71875" - a difference of .28125, or 1/4")
I have 1/2" plywood and skids rarely touch the E-Track, and have never gotten hung up in it. The original powder coating on...