5mm jack leaving some of the metal exposed. I was skeptical at first since all the ratings have no reviews attached to them but I?m happy with what I got! Most comfortable flip-flops Ive ever had and being in Florida for 50 years, thats a lot of flip-flops. Lightweight and easy to handle. I am still in search of the "perfect" pillow for me. Now, the bad. This product was one of the expensive ones I researched, but the reviews helped me make my decision. I only got them yesterday and havent charged them yet, but Ive had around 8 hours listening time so far and they are still going strong. For shorter listening periods, I prefer the Solo Pros to both the Solo3s and my Sony 1000xm3s. Hopefully he puts it to good use!