OFD Quality steel lateral files are built for high-activity filing in corporations, educational institutions, hospitals and government offices. Inner frame and heavy-duty ball-bearing suspensions stand up to years of use. The interlock system inhibits more than one drawer from opening at a time. Counterweights are placed in most models to prevent tipping. Filing includes side-to-side hangrails for letter or legal filing, adjustable leveling glides, and removable lock cores.