1U or 1RU stands for “1 Rack Unit.” Think of it as a single slot or shelf space in a big bookshelf. In the world of server hosting, we use these ‘slots’ to stack equipment in a neat and organized way. If we liken our racks to a bookshelf, then 1RU is like a section that measures ~44.5mm in height. Our cabinets (47U Rittal model 5513110) are 2200mm tall, 600mm wide, and are set to a depth of 800mm, so when you get a 1RU space with us, your equipment will fit into that 44.45mm tall slot within those dimensions. If you get full rack cabinet, you will get all usable space (42U) for your use.
If this is still a bit confusing, don’t worry – you can just send us the brand/model of your equipment and we’ll be happy to assist!