The Listing has revealed the design of the device along with some of the key specifications. According to the TENAA listing, the device has a 6.55-inch OLED screen and measures 160.8 x 75.2 x 8.5mm. There is a punch-hole camera cutout on the top left corner of the screen.

The device has a 2,200mAh dual-cell battery. We can see there are four camera sensors on the rear side so we can assume that the device is having a Quad rear camera setup. It is certain that the device will be available with Android 10 with Realme UI at the top of it. Source

Mysterious Realme RMX2121 spotted on TENAA  could be Realme X3 Pro - 48Mysterious Realme RMX2121 spotted on TENAA  could be Realme X3 Pro - 21