HC-06 Bluetooth Serial Module RS232 TTL for Arduino

http://www.martyncurrey.com/hc-05-fc-114-and-hc-06-fc-114-first-look/

http://www.martyncurrey.com/category/bluetooth/

http://www.martyncurrey.com/bluetooth-modules/

Bluetooth HC05- How to pair two modules

https://alselectro.wordpress.com/2014/10/21/bluetooth-hc05-how-to-pair-two-modules/

https://hackaday.io/project/1278/instructions

https://arduino-info.wikispaces.com/BlueTooth-HC05-HC06-Modules-How-To

Modify The HC-05 Bluetooth Module Defaults Using AT Commands

http://www.instructables.com/id/Modify-The-HC-05-Bluetooth-Module-Defaults-Using-A/