Very comfortable, not slippery. Will update review if I have any issues. Not the best packaging. Now there is another problem. Carabiner does not feel secure at all. My toddler lives in these! This product turned out to be what I was looking for. When placed inside properly (which isn?t hard to do), the pins connect to the plates on the earbuds to recharge them. Pros:* Good sound quality and not bad sound when sitting or exercising in a space with not a lot of wind or very loud noises. The other day, there was an argument in the car next to mine, not even 20 feet away that involved the police once the train had stopped, and I DIDNT EVEN NOTICE BECAUSE OF HOW WELL THE NOISE CANCELLATION WAS.