These clips are designed to be used with our Universal File Bar Economy Packs. Additional clips mean you can create multiple bars used in any combination: side-to-side, front-to-back, letter or legal allowing you to design your own Universal File Bar System. Remember, combining "Flush Mount" and "Hanging Mount" clips within one drawer can increase the versatility of the Universal File Bars greatly. This is especially true when designing drawer layouts for a wood lateral file cabinet.