These are feet for your steel socket rails to get them to stand up straight in your toolbox. You can use as little as one, or you can use 2 to make it symmetrical. It's a tight fit, so just push it on hard! Didn't want it to fall off. You can always scale it to fit if needed. There are 3 versions

Wide Versions:

1. Socket Rail Feet - Socket rail that is solid and prints fast
2. Socket Rail Feet No Coring - The same as above with some coring to make it look fancier. Takes longer to print

Compact Version:

1. Socket Rail Feet No Coring Smaller - A more compact version since the large one takes up a fair amount of footprint.