Heavy duty 4 ft x 4 ft quick assembly tray stand. Absolutely no tools required. Can be assembled in 5 minutes or less.Accommodates all popular brand (ID) trays and reservoirs including Flo-n-Gro, Duralastics, Botanicare and more. Overall height is 25 in. Height from bottom bar to floor is 18 in without casters. Outside dimensions: 53 in length by 53 in wide. Inside dimensions: 51 in length by 51 in wide. Tray sold separately and may fit differently depending on brand. US Patents 8,714,498, D756,690 and 9,084,478; Chinese Patent 201280018267.2; Patents Pending 29/562,014, US20150320200, AU2012290715, EP2725947 and HK1193554A; and PCT Application WO2013/019268.