This depth adapter kit lets you extend or reduce the mounting depth of one rack unit (1U) in your server rack by up to four inches. If you're using the adapter kit in a two post installation the extenders can support a total weight load of 10 lbs. (4.5 kg). If you're using the adapter kit in a four post installation, the extenders can support a total weight load of 90 lbs. (40 kg), you can even use two sets of extender brackets in a four post installation and achieve the same weight capacity performance. This TAA compliant product adheres to the requirements of the US Federal Trade Agreements Act (TAA), allowing government GSA Schedule purchases.