Caller ID was "Arvin CA."  Presumed telemarketer.

Robocall offering a "free" wireless security system with no charge for equipment or installation.  No, I don't think so.  The hassle we have with smoke detector batteries multiplied by the number of sensors in our security system?  Sensors easily jammed?  I don't think so.  And, we all know that "free" really means "included in other fees and costs."  Oh, yes - since these people autodial robocalls without DNC filtering from a VOIP boiler room, you have no reason to believe that you will be able to find them again after you let them debit your credit card...
Caller ID is "Arvin CA" as reported here previously, number is a Bandwidth SMSEnabled VoIP in Arvin, CA.  Blocked.
Anyone who is interested in a security system, know that wireless is, at best, a last resort if you can't install a wired system.  Scammers offer it because it's cheap and installed in a few minutes with a stepladder and screwdrivers.  It's worthless against burglars who buy a jammer off the dark web.

This call came 5 minutes after I Left a message on my client's phone.  It appear that these scammers even monitoring our phone.

Telemarketing pond scum

We just bought the same phone system from Costco.  LOVE IT!  BTW, I just blocked this number.