1 BT Shield v2.2 (Master / Slave) : Stackable Bluetooth Shield
1 Bluetooth Shield (Seeedstudio)
3 4duino HC-06 wireless module for Arduino
4 Bluetooth HC-05 module RF transceiver Master en Slave
http://www.beta-estore.com/rknl/order_product_details.html?p=393
http://www.antratek.nl/bluetooth-shield
http://www.seeedstudio.com/wiki/Bluetooth_Shield
https://www.reichelt.com/de/en/4duino-hc-06-wireless-module-for-arduino-arduino-hc-06-p170171.html