Google nexus 4 Quick Start Manual page 86

Symbol Description
do not expose your device or its accessories
to open flames.
do not expose your device or its accessories
to magnetic media (floppy disks, credit cards,
etc).
do not expose your device or its accessories
to extreme temperatures, ie below -5 and
above +50 ° c.
do not expose your device or its accessories
to liquid or moisture.
Not groped to disassemble the device or its
accessories, only authorized personnel can
do it.
 Nexus 4 quick start guide