Panasonic KX-TES824 Advanced Hybrid PBX System can cost effectively support all your personal and business communication needs. The system supports 3 outside (CO) lines and 8 extensions - all built-in so you can use the system straight out of the box. With optional cards, you can easily expand the capacity up to 8 outside (CO) lines and 24 extensions as your needs grow. The system provides features that can satisfy the demands of the most sophisticated and cost conscious users. You can even connect a variety of communication devices, such as cordless phones, answering machines, computer modems, credit card verifiers, fax machines, and any other device that works with conventional telephone lines.