Download Solo S450 Official Firmware
Learn How to flash/unbrick Solo S450
From here
Solo S450 Specs
Chipset
Dual Core MT6572 @1.3GHz, DSDS
Memory
16GB eMMC ROM + 1GB RAM
Dimension
131.5 x 66.5 x 10.5 mm
Network
GSM/EDGE: 850/900/1800/1900
WCDMA: 900 /2100
Display
4.5" FWVGA IPS display
Features / Interface
3.5mm audio jack
Micro USB
Micro SD Card slot
Bluetooth , WIFI
GPS/AGPS
G-sensor, Proximity and Light sensor
Camera
5MP Main + VGA Front
(Adv. Imaging Support )
Other
Premium headset & case included.
Battery Size
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