Identity label (7)
'identity label' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for name tag that I've seen before include "Personal identification" , "verifies one's identity" , "Label to identify" , "Label proving ownership" , "sign of identification" .)
(Other definitions for nametag that I've seen before include "It may identify" , "One helps identify" .)