Really good at blocking out house hold noises like people going up and down stairs, slamming doors, music, coughing, TV's, dogs barking, traffic outside etc.
I still hear my alarm though and the smoke alarm.
Also they really are soft so are comfortable to sleep in.
I used to wake up like 20 times a night, now I sleep straight through. So if you have the same kind of problems then get these they work really well.