If you've ever run into the problem where your large (6.3mm) headphone jack won't fit your phone, then you'll know how annoying it is. The reverse can also be just as annoying. A jack adapter, that converts one connector into another, is always worth having around just in case. In addition to all possible plug adapter sizes, we have headphone adapters that turn small jacks into big jacks, big jacks into small jacks, straight jacks into right-angled jacks (ensuring that the plug doesn't stick out) as well as splitters, so you can plug two sets of headphones into one phone ouput!