A vibrating ear patch could help thousands of people who are living with hearing problems.
The stick-on device transmits sound waves through the bones of the skull to the inner ear for processing into sounds.
This bypasses the damage to the outer and middle ear that can cause deafness and prevent some people from being able to use conventional hearing aids.
Around one in six Britons — some 11 million people — suffers from a hearing loss, which occurs when problems in the ear or auditory nerve stop sound signals from reaching the brain.
The most common type of deafness, which is called sensorineural hearing loss, is caused by damage to the inner ear or the auditory nerve, which carries information from the inner ear to the brain for conversion into sound.
The second most prevalent form — conductive hearing loss — occurs when sounds cannot get through the outer and middle ear to the inner ear.
People may also have both conductive and sensorineural hearing loss.
Conductive hearing loss is usually caused by an infection, a perforated eardrum or an unusually narrow ear canal.
Conventional hearing aids help some people with conductive hearing loss, but most people choose to use bone conduction devices to allow them to hear without using their outer or middle ear.
But, until now, many of these devices have involved needing a surgical implant.
The Adhear device is implant-free and consists of a triangular patch and an audio processor.
The water-resistant patch is stuck on the skin behind the ear and the processor, which is around the size of a small eraser, is attached to it.