'SIMPLE & EASY INSTALLATION: Rackstuds install from the front for easy installation. Simply insert the stud, install the yellow lock washer, and hang your gear. Spin on the nut - job done in less than 30 seconds! STRONG & SAFE: In addition to its simple installation, Rackstuds can withstand shearing forces of over 400 pounds. Rackstuds are safe, won't scratch your equipment, and don't pose an electrical hazard. No more fiddling behind the rack with cage nuts! THE GO-TO CHOICE FOR DATA CENTERS WORLDWIDE: With over 1.5 Million units sold, The Innovative New Rackstuds Series II builds on this reputation and is now Stronger and Faster to insert, with longer threads. Rackstuds provide a place to support your gear, making single-handed installs possible Rackstuds are much simpler, faster, safer and very strong Hole Size: EIA-310 requirement 90.5mm/0.374'' Rail Thickness: EIA-310 Not defined Rackstuds RSL3.2Rxxx-S2 2.7mm-3.2mm/0.106-0.126''