-Studies show you can use the various sizes based on your activity and the amount of hold and isolation you would like. For example while resting a great hold is not needed like as in gym activities. -Specialized material conforms easily to the shape of your ear canal which makes for a comfortable fit that reduces ear fatigue and stays in place during activities. The Eartips are specially design to fit tighter and more snug, in order to provide a better connection and hold to the In Ear Earphone Driver. 3.Apply pressure and with a circular motion, twist with one hand clockwise and with the other the opposite direction, until the ear tip has fully covered the Driver of the Earphone. Also to help with installation if needed, you can slightly moisten the rim of the ear tip canal, and repeat.
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