These are great headphones. They isolate external sounds well under the condition that you hear also music but not necessarily high. A 30 to 50% should be enough to isolate almost everything. Without music playing they just reduce external sound but not that much. Sound leakage is minimum. With maximum volume they barely leack any music so they are great for times and places were you don't want other people to be disturbed your music. Comfort is also excellent but they do look big on your head eventhough they are really light.So why not 5 stars...