Quick caliper question
 

Just wondering if the L on this rear caliper indicates it is the left (driver's side) one. Not feeling like taking my wheel off for the third time in 2 days.

Also why the heck is there a radioactive symbol on the thing? haha

The markings on it are as follows (in order as they apear)
L *radioactive symbol* 2 T
10-14 AD35P
13 15
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