I wanted this item because I wanted to go running and use my palm treo as a music player. Everything about this product is excellent, it fits in the ear and comes with an adapter that converts the 2.5 to a 3.5 input. The only problem is I got screwed by its sophisticated adapter. There is a screw pattern towards the bottom of the jack thats used to screw into the adapter. This is good in that the adapter will NEVER come off and its shut tight but when I try to plug it into my palmtreo (2.5mm) it doesn't go in all the way because of the screw pattern. In order to use it for my treo I have to use the adapter (3.5mm) and then use my own adapter to convert it back into 2.5mm. It works but I had to modify it and when I go running I have to make sure my phone is fully charged if not it will die fast because of the two adapters.