EarLocks fit securely to original Apple earbuds and most circular earphones (model also available for Apple EarPods). The patented EarLock retention rings comfortably lock into key points of your ear to hold earbuds securely yet comfortably in place. Earbuds will no longer have a problem staying put. EarLocks are ideal for an active lifestyle like jogging or cycling. This near-perfect fit will optimize the fidelity of the music delivered by your phone or other mobile device, since the earbud is now nearer to your canal opening. And the durable, hypoallergenic, medical-grade polymer is comfortable against your skin and maintains its shape for long-term use. One size fits most everyone.