The Transmitter Pager is a communication device used by Nick Fury, an ordinary Earth pager modified by Carol Danvers using Kree technology for use as an instrument of last resort in extreme emergencies. Fury was eventually forced to use it in response to the Snap.
Nick Fury's Pager
The pager was used by Nick Fury who took pride in possessing a state of the art communication device. Fury used it to call S.H.I.E.L.D. for backup when he and Vers were detained in a Joint NASA USAF Facility. However, since Keller was replaced by Talos, Vers confiscated the device from Fury so he would not make another similar mistake.
- "I thought we bypassed the battery."
"We did. It's still plugged in, it just... it just stopped."
"Reboot and send the signal again."
"We don't even know what this is."
"Fury did. You tell me the second you get a signal. I wanna know who's on the other end of that thing."
- ―Steve Rogers, James Rhodes, Bruce Banner, and Natasha Romanoff
Following the battle at Mar-Vell's laboratory, Carol Danvers upgraded Nick Fury's device and gave it back to Fury shortly before departing. Danvers assured Fury that the device could reach her even if she would be in another galaxy, but insisted that he should only use it in case of absolute necessity.
Even with the Avengers divided and any hope of a coordinated defense ruined thanks to the Sokovia Accords and the Avengers Civil War, Fury was not willing to use the device just yet, noting to Maria Hill that they would never need to call Danvers if they did their jobs right.
However, in 2018, a threat emerged, courtesy of Thanos, which the Avengers were unable to mount an adequate defense against due to a disastrous combination of the power and resources possessed by the Mad Titan and the schism caused by the Avengers Civil War, leading to the Snap. While witnessing this catastrophe, Fury sent a distress call to Danvers through the Pager, before succumbing to the Snap himself.
The Transmitter Pager was later somehow retrieved by the surviving Avengers. Sometime before the rescue of Tony Stark and Nebula; Steve Rogers, Natasha Romanoff, Bruce Banner and James Rhodes examined the Pager at the New Avengers Facility when it suddenly went inert, which confused the Avengers, as they had it powered externally. Romanoff proposed that the quartet find out who Fury was contacting before Danvers approached them in distress, asking for Fury's whereabouts.
- Telecommunication: Upgraded by Carol Danvers, the Transmitter Pager was able to send messages on the galaxy-range distances. However, it will automatically cease sending messages or even signals in the event that the receiving end happens to be already within range proximity of the transmitting device.