I looked a few times and can't see where they have such a feature.
Im wondering if they are worth the $30 on Amazon or is it better to shell out the $20 extra for either the Shure SE110s or V-Moda vibes. My primary concern is noise cancellation effectiveness (im using these as travel earbuds) and build quality as im going to be using them pretty often and i don't want them to die out as i've had a few other pairs.

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