This rack mount comes with 1 empty slot for 1 Raspberry Pi. Fits below models:
There are also 2 spaces for 2 connectors.
For these 2 inserts for connectors, you can optionally choose LAN (item no. 8719992970087), USB3 (item no. 8719992970148), USB-C (8719992970162), Audio (8719992970131) or HDMI (item no. 8719992970124). Blank inserts are available also (search for 8719992970247)