The Vintage General Electric MASTR Radio Base Station Shelf is a piece of surveillance and alarm equipment from the United States. Made by General Electric, this two-way radio parts and accessories item is a GE product with the model number MASTR. Despite being untested, this base station shelf is a valuable find for collectors or those looking to restore or repair vintage communication systems. Its sturdy construction and historical significance make it a unique addition to any facility maintenance or safety project. Vintage GE Mastr Executive Base Station Transceiver. Handheld monitor not included. When monitor switch on console is pushed you can hear a buzzing sound out of speaker that adjust with volume. Other than that I know nothing about it. Please see pictures for details and conditions. What you see is what you will receive. SEE MY OTHER LISTINGS AS WELL.