It allows you to mix all your audio into one source using software! You can feel the metal pushing into your foot which takes away the effort that has gone into these to make them comfortable. Love the style, quality and durability of Clarks. I apparently bought this while I was a few sheets to the wind and was surprised when it showed up. One thing I wish these headphones had is a volume controller so I dont always need to fiddle with the volume control on my phone. The sandal is prettier in person and is very soft. The delicate mechanisms within the ear that enable us to hear can not survive the high air pressure level that is produced inside the car when the airbags deploy. The silver part feels like some type of fabric but its okay because its for ky daughters dress up! And 2, whatever you do before buying this please for the love of god, or more importantly your son or daughter whos going to be sitting on the bike with you,,, please check to make sure that your bike does NOT have the rear brake and gear cables run along the top of the top bar. (best way for me to explain it).