about Bluedio New Version R+ Bluetooth Stereo Hi-fi Headphones?

i want to buy Bluedio New Version R+ Bluetooth Stereo Hi-fi Headphones on amazon i want to know what does the R+ bit mean this is the headphones on this website



http://www.amazon.co.uk/Bluetooth-Headphone-suppression-Bluetooth4-0-Multi-Media/dp/B00E16T4OC/ref=sr_1_1?ie=UTF8&qid=1385896777&sr=8-1&keywords=Bluedio+New+Version+R%2B+Bluetooth+Ster eo+Hi-fi+Headphone+Supports+NFC+aptX%C2%AE+audio+suppres sion+solution+Bluetooth4.0+8Tracks+headset+Support +Line-in+Mode+Multi-Media+Playing+Micro-SD+Card+%2832GB%29+Music+Playing+%28White%29