Explosion proof telephone KNEX2

Features
Analogue telephone matching with most PABX, PBX and PAX system
Robust body vandal resistant
Busy tone detection for auto release the line if line busy
Dry contact for external control automation 
Auto answer
Full Soft lock: only dial out from phone book *0 memory address number
Half soft lock: limit to dial out starting number, e.g. “****2” area code
High temperature approval 
Ring sound *5 dB dfd in 1 m and *0 ringing tone melodies selectable
Listening by loudspeaker: *0dB in 1m
Phone book memory: *0 address ( name & number) programmable
Stainless steel keypad for dial and manuel
Magnetic reed hook-switch
Telephone line powered. No external power or battery required