DLK-10 Tweeter Protectors are designed to virtually assure that you’ll never blow your Yamaha NS-10M studio monitors’ tweeters. DLK-10’s are dynamic devices, only becoming electrically “active” when signal current levels dictate. But at volumes that don’t endanger your tweeters, they’re invisible, electrically speaking. A pair of DLK-10 Tweeter Protectors sells for less than the cost of just one replacement tweeter and installation takes just a couple of minutes. They’re warranted against failure for one year (the DLK-10s, not your tweeters).