Radar

The Radar is a technological device used by Mamas and Sisters, possibly created by the "Demons". The radar can locate and show where people are through the transmitters even at long distances. The radar made its debut in Chapter 2 of The Promised Neverland Manga and Episode 2 of the anime.

Introduction Arc
When Mark reported how he lost sight of Naila during a game of tag, Isabella used her radar to track the latter down. Isabella went into the forest to search for Naila and came back with the lost child shortly after. Emma and Norman are stunned by how fast Isabella was able to find Naila, as they were soon able to determine the device she uses to be a radar, which they initially thought it was a pocket watch.undefined

After some time, Emma and Norman were surprised at how Isabella would go to the extent of using a radar to control them. After Isabella confronted Emma

Appearance
In general, the radar resembles a pocket watch, being in a circular form with a cover, which protects the glass part of the radar. On every radar, there are marked designs, which indicates where the transmitter holder is, as quoted by Krone.

Disadvantages
So far, the radar appeared to have only one disadvantage, as mentioned by Krone, is how the user cannot identify the orphans each mark on the screen of the radar represent.undefined Nevertheless, the disadvantage does not restrain the radar from tracking down individuals from far distances.

Despite the radar's disadvantage, Isabella is one of the users who are quick to overcome it, as she could determine which orphan a mark represents by the speed of the mark, such as identifying two marks to be Norman and Emma due to their speed.undefinedundefined

Users
Several people have been seen using the device throughout the series: It is also further implied that all the other Mamas and Sisters in the other plants at the Grace Field House also use the device to locate the location of the orphans.
 * Isabella
 * Krone (formerly)
 * Grandmother