I prefer the kind with the string that block out sound better. I use these when I'm sleeping to block out noises. I also live right by a busy street and the traffic noises can be a bit hard to make it sleep. We've even had road construction work at 1 AM.
Thanks dear. I use to use these but found some ear plugs that work better on amazon and I like how they block out sound much better. These are the type of earplugs they hand out at my sister's church. I went there for Easter services last year and it was like attending a loud rock concert.