These people will hound you relentlessly to subscribe to their magazine, HVACR  a technical publication for the heating /
air conditioning industry. do not accept their trial publication or you will never get rid of them.

I believe this is a vendor who handles renewals, etc for many different types of magazines. I work in the fire service and they were trying to get us to renew 6 months early for a publication we subscribe to. They call relentlessly even thought we've asked to be taken off their call list. Lately they disconnect when we answer. Perhaps, just to annoy us?