fuel line bracket question

[wazzabie]

What is the blue thing between the two mounting bolts for the steel lines?

http://i165.photobucket.com/albums/u59/jl4punch2/DavisAutoSports/80_GMC_JIMMY_RED/file-150.jpg

 

[dyeager535]

Is it an ID tag (what GM used to note part number)? Looks like there is a red one on the return line just to the right in the picture as well.