If you have a number of leads to label, studio leads if you're a musician, or several battery chargers in a muddle, you cannot do better than to buy a pack of these. Just make sure, unlike the previous reviewer, that you buy an EXTRA FINE TIPPED MARKER PEN, DESIGNED TO WRITE ON PLASTIC. Staedtler's example of the genre, also for overhead projectors, is my weapon of choice: it's a 'staedler permanent lumocolor S dry safe ' permanent marker in black, and it does the job a treat. Pentel fine tips on permanent markers write like blackboard chalk and are best avoided by this reviewer. Write the label, loop the Cable Tie around the cable, thread through, pull almost tight, and then cut the surplus with scissors. You get more than you'll ever need in the pack, so if there's a problem first attempt it really doesn't matter. Hope this helps, please don't be put off by other reviews.