Your colocation can host any combination of small IT devices, as long as they fit into your rack space in a reasonable arrangement.
A reasonable arrangement means that the devices including cables are statically stable in the defined length x width x height cuboid space. The cuboid walls can only carry very small weights, the main load must be taken up by the floor. Examples can be seen in the pictures next to the order dropdowns. Not part of the rack space are 230V power supplies, which you may have to include due to the AC 230V Socket booking, so they do not play a role in the space planning.
Small IT devices means devices that have an information technology purpose (from data processing to data storage to sensing to …), such as a single board computer and a USB hard drive. A hair dryer that produces hot air is not included in this spectrum. Mining-focused hardware is also not allowed due to its high power consumption. Normal single board computers with thick GPU like the Jetson Nano are not affected by this restriction and can of course be installed. The boundaries are unfortunately fluid in this context, please contact us in case of doubt before booking.
In order to be able to use your devices, at least one network-compatible computer should be part of your device combination, which is then addressable from the Internet via IPv6.
Example configurations can be found in What does a typcial colocation setup look like?