Sierra Wireless AirLink RV50 questions

Hi,
Apologies if this is the wrong sub.. I looked around.
I recently came into possession of one of these RV50's & see they go for over $500 on eBay etc..
What are they for, how are they used?
Trying to see if there's an application in my office (small) or at home or if I should just sell it.
Sierra Wireless AirLink RV50 D 3.0

Thanks in advance