Each module snaps into the socket magnetically, and its fool proof to insert/remove each piece. I bought a Large and it fits just the way I want it too - loosely and long. I liked it because I like the brand but once I got to use it I noticed that it has so much voice going on but the product is great. The feedback was that they are the best patio/pool shoes ever ! The nuts and bolts are machined so poorly that youll destroy your hands trying to assemble certain parts of it. You have to hear so much each time you put them in your hear its annoying. Mine are more loose now than when I first received them which was about 1 month ago. Most earbuds dony fit ears properly, at least if you follow the manufacturers guide. What more, the sound quality is good, recommend this headset to who works from home at this special time like me. I like the sound and they do a good job of blocking out or cancelling sound from outside if I?m on the treadmill or mowing the lawn.