I'm using earplugs to sleep (and to focus) for more than 25 years now. For a long time I've used the Quies Natural Wax earplugs. Some years ago I switched to Oropax Classic earplugs. Both are made of natural wax. Wax earplugs are easy to fit in your ear and don't press against your inner ear like foam earplugs. Oropax earplugs are a bit bigger than Quies, so they don't just seal your inner ear canal but also a small part of your auricle, providing an extra buffer against sound while still being comfortable.