Netgear’s Arlo Pro 2 home security cameras are among the few that can run completely on battery power, and the newer Pro 2 models add additional touches that the original Arlo cameras liacked, like 1080p recording, rechargeable batteries (rather than watch batteries), improved motion detection, two-way intercom, and a base station with 100 decibel alarm. So if you’re ready to start monitoring your home like a paranoid person, Amazon will sell you the two camera starter kit for $339 today, down from the usual $360-$440.