Where did you get them from? I had some made to measure from the ear dept at specsavers or somesuch place and they’re “ok” but slip out v easily (originally had them made to aid sleep and watch F1 trackside (some say the two could happen at the same time but I disagree...)).
HB
Here in Germany my bought a pair from "Amplifon.com". Very reasonable price. She uses them since more than 5 years. They fit like a glove.
Google shows a company with the same name in GB....
