I hammered them into a red hot steel nut to determine the size of the ring. Start small and grow. I used a regular steel hammer and it smoothed out the small area on the bearings where I hit, but that's to be expected. Otherwise they worked great.
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Most Popular Sizes: 8 kinds of sizes include 3/4", 5/8", 9/16", 1/2", 7/16", 3/8", 5/16" and 1/ 4 inches, 1 of each size