2000h Durable Communication Switch 4-32 Extensions Telephone Exchange. Expandable Structure: Supports 4 to 32 extensions by adding PSTN and extension line cards. Comprehensive Call Management: Features PC software for billing, hotel management, and call duration control. Flexible Customization: Offers flexible, minor, and full customization options including designs and samples. Advanced Call Features: Includes call transfer, forwarding, three-party conference, and busy transfer. Auto Attendant Service: Supports custom outgoing messages and auto-attendant answering modes. Call Permission Control: Manages call classes, forbidden numbers, and exclusive CO line access. OEM and ODM Services: Provides full OEM and ODM services with flexible customization capabilities. Backup Power Support: Compatible with UPS backup batteries for continuous operation during power off.