The Yeastar S2 module is a professional telecommunications accessory featuring 2 FXS ports for voice communication systems. This module allows the connection of analog telephone devices to IP-based PBX systems and provides reliable voice transmission with clear audio quality. Built with industry-grade components, the S2 module offers stable performance and consistent operation in business environments. Its compact design measures approximately 100 mm in width, 25 mm in height, and 120 mm in depth, weighing around 180 g, making it suitable for space-constrained installations. The operating temperature range extends from 0 °C to 40 °C, ensuring reliable performance under typical office conditions. The module supports standard telephone features such as caller ID, call waiting, and DTMF tone recognition. Installation is straightforward with standard RJ11 connectors for telephone line connections and a network interface for system integration. Power consumption remains low at approximately 5 W during normal operation. The matte black finish gives it a professional appearance while minimizing the visibility of fingerprints and dust. This module is compatible with various Yeastar PBX systems and requires proper configuration through the system administration interface. Each FXS port can support one analog telephone device, making it ideal for small office setups or expanding existing communication systems. The robust construction ensures long-term reliability with minimal maintenance requirements. Technical specifications include support for G.711 and G.729 voice codecs with echo cancellation and voice activity detection for optimal call quality. The module undergoes comprehensive testing to meet industry standards for telecommunications equipment.