Dexcom expiration?

I have Dexcom transmitters a 2 G5 sensors sitting in their original boxes from roughly late 2014 to earl 2015. Where can I find the expiration dates on them? There's an "SB 2016-07-30" listing on the back of some of them but that is the only date I can find. Is SB the expiration date?

EDIT: Deduced that that is in fact the expiration date so the next question is, are they still safe to use? I have transmitters that expired in 2016 (G5) and sensors that expired in 2015 (probably 3 full boxes worth). What is it about the sensors that expire? They are literally just adhesive and a needle.