The number of ReX range extenders connected to the Ajax security system depends on the hub model:
| Hub | 1 |
| Hub Plus | 5 |
| Hub 2 (2G) | 5 |
| Hub 2 (4G) | 5 |
| Hub 2 Plus | 5 |
| Superior Hub Hybrid (2G) | 5 |
| Superior Hub Hybrid (4G) | 5 |
Only hubs on OS Malevich 2.8 and higher support the connection of several ReX.