Works for my micro phone charger because the cord is very thin and consistent in size. Not so great for earphones because they have a place where the cord widens ever so slightly and they won't go in past there, leaving too much hanging out and able to tangle. Not good for long cords, and definitely not for any cord as thick as a light cord.Sirven sólo para cables cortos y finos. No sirven para audífonosThis product is a total disappointment. The unit halves come apart too easily. If you are able to get your cord in the slot, you need pliers to turn the dial, and you need a clamp to hold the halves together.flimsy plastic, winding center pops out when winding, only hold the slimmist and shortest lengths of a cable - think earbuds or small short mouse line; "locking" slide is only good if there is hardly any cable in it.got these for stocking stuffers - OH Well ...I got stuffed all right.....this product is as described by vendor, however the lid did not stay closed and the cable would come out of the device which was not the way this was intended to work.Just wish they could/would make one for 10ft cords. This size is probably great for smaller cordsThis was a huge disappointment of a purchase. It fell apart and broke. I tried several of them, since I had purchased nine. The courts do not wantUsed these for travel to keep cords organized. Came apart on second use. Very flimsy and cheap with sharp plastic edges