Busy Lamp Field 40 BLF / 90

The Busy Lamp Field 40 (BLF / 90) is an advanced expansion module used in enterprise telephony systems to provide visual indicators for call and presence status of multiple extensions. It features 40 programmable BLF keys that help operators, receptionists, and power users monitor the status of internal lines (busy, idle, ringing), speed-dial frequently used contacts, and quickly access call control functions. Designed to integrate with compatible PBX systems and key expansion modules, the BLF / 90 enhances productivity and simplifies call management in busy communication environments