Why does the display have CL4940 on it?

My display has the date and time, but why does it display the model number of the phone? Is there a way to turn it off?

crwdns2934089:0crwdne2934089:0 crwdns2934093:0crwdne2934093:0

crwdns2934109:0crwdne2934109:0

crwdns2889612:0crwdne2889612:0 0
crwdns2934285:0crwdne2934285:0