1,DS9490R iButton reader 2,Maxim original 3,can be plugged into the DS9490R USB adapters and all the DS9097U-XXX serial-port a iButton reader of DS1990A-F5This is the most popular Blue Dot as it contains a male RJ-11 plug at the other end of the cable. It can be plugged into the DS9490R USB adapters and all the DS9097U-XXX serial-port adapters. iButton reader DS9094R original