Lenovo S850 Guide De Démarrage Rapide page 5

Installing the Micro SIM card
A Micro SIM card provided by your carrier is required in order to use
cellular services. Install the Micro SIM card as shown.
Insert the SIM eject tool that comes with your smartphone
Step 1.
into the hole in the Micro-SIM-card tray.
Pull out the Micro-SIM-card tray and position the Micro SIM
Step 2.
card into the tray in correct orientation.
Carefully insert the tray with the installed Micro SIM card
Step 3.
back into the slot.
Only Micro SIM cards work with your smartphone.
Always turn off your smartphone first before you insert or
remove a Micro SIM card. Insert or remove a Micro SIM card
with your smartphone on may damage your Micro SIM card or
smartphone permanently.