These are Flanges protruding from the front panel of a piece of a Dell rackmount servers that are used to secure the item to the rack rails. In some cases, these are extended parts of the front panel of the item.
If you ever need a single or a pair for a particular Dell model, you have come to the right place. We stock these rackmount ears for most R-Series Dell servers. If for a reason we do not have what you need, please contact our sourcing team and we will source the correct part for you.
A simple video tutorial on how to change rackmount ears.