Blue box under rear window panel?

I was changing the RF receiver on my Rangie this weekend for the new model (sick and tired of the old flat battery syndrome at inconvenient times!) and I saw this blue flat plastic box with various co-ax type cables etc connected - what is this? Some sort of rear pre- amp / driver for the Harmon Kardon sound system??

its the tracker reciver that the previous owner installed so that the vehicle can be stolen back...

its a dealer special....

i thort it was the radio signal amp

Radio amp, as the aerial is in the glass rather than a normal aerial and doesn't produce such a good signal so needs an amplifier. Nothing to do with Harmon Kardon, Christian Dior or any other fashion accessory LOL

My Rangie has a HK sound system I thought they all had? So what's your Christian Dior one like the LOL

I thought it may be audio related, thanks for that. I'll just leave well alone as the radio is perfectly functional! So much for thinking one could slide one radio out and just fit another one in its place!