These PSU mounts install directly on top of the Antminer without tools! They lay directly in the grooves on top of the miner. The PSU mounts are powder coated to prevent scuffing or damaging your antminers and PSUs! These shelves have been tested and guaranteed to fit: Antminer S9 Antminer D3 Antminer L3+ Antminer T9 (Other Antminers using the similar chassis should not have any problems either! If it doesn't, you can return the unit with our 30 Day Money Back Guarantee!) Back Story In our mining operations we discovered power supply management was tricky while keeping our rigs and PCIe power cables short and cool. We were surprised the AntMiner APW3++ PSU had such surprisingly short cables! This shelf makes APW3+ PSU look like it was made for it! Check out photos! Plus, putting the PSUs on the side got in the way off MORE miners! The PSUs generate heat, so we wanted to avoid placing them to close to surrounding miners to keep the mining rigs cool! This mount puts the PSU heat away from the miners! By moving the PSU up top we were able to maximize the numbers of rigs on a shelf! Increasing miner density and promoting better cold to hot airflow! Happy Mining! ArcMyn Team!