My son is now 1 we got these when he was 10m old. I trained him to keep them on by having him wear them in his highchair facing the sun.  They are great because you can put them on in any direction there is no right side up. My son has worn them for 4 hours at a time and seams happy with them. I do not use the cord with them. His head is 22%ile - and they fit fine.