This is a pager. It's very small. The black device has a green screen and several buttons. The number displayed on each screen is different depending on the platform. Pager is the most popular communication product in the 1980s and 1990s. It can make calls and send messages. At present, people no longer use it, but more for collection and commemoration, so it also contains the meaning of reminders, warnings, communications, nostalgia and retro. Apple Platform: 555-3215, in the United States, 555 has been used as a virtual or fake phone number. Facebook Platform: 543-4800, (650) 543-4800 is the customer service phone number of Facebook. Microsoft Platform: unrecognizable. Samsung Platform: 954-5684. Twitter Platform: 40404, it is the SMS number that Twitter has terminated. JoyPixels Platform: 553-6654. Google Platform: 1998, the founded year of Google. LG Platform: 0018190-. Mozilla Platform: 555-5555, also a virtual number. WhatsApp Platform: 867-5309, "867-5309 / Jenny" is a song released by American band Tommy Tutone in 1981, this song was very popular at the time.