PC Cases & Drive Cases
Tripp Lite 4POSTRAILKIT1U 4-Post 1U Universal Adjustable Rack-Mount Shelf Kit - Silver
Supports UPS systems in 4-post rackmount applications Adjustable to any length between 20.5 and 36 inches Square hole rack attachment hardware included Supports weights up to 150 lbs
https://www.bizrate.co.uk/tower_drivecases/tripp-lite-4postrailkit1u-4-post-1u-oid7157178730.html