Two-wire stations include the N-8000MS Multifunctional Master Station, equipped with a 32 character alphanumeric LCD display, handset and speed dial functions; the N-8010MS Standard Master Station with keypad and handset; the N-8020MS Industrial Master Station, built to withstand severe environmental conditions; and the N-8011MS Hands-Free Master Station offering hands-free simultaneous two-way (duplex) communication via an innovative ambient noise sensing function. Other two-wire stations include the N-8031MS Flush-Mount Hands-free Master Station, N-8050DS Indoor Sub-station and Q-N-8050WP Outdoor Sub-station. For custom station applications, TOA offers the N-8031SB Hands-free Master Station Board Unit and the N-8050SB Hands-free Substation Board Unit. Station line monitoring is also available via software, web browser or station display.