Acupressure is an ancient form of healing that uses finger and hand pressure to stimulate key points on the body. Several of these acupressure points can be effective for preventing and relieving motion sickness, however by far the best known - and easiest to locate and use - are the P6 points (also called the Nei Kuan points), which are located on the inner wrist.
Acupressure wristbands (also known as morning sickness wristbands) use this acupressure principle - the small stud on the bracelet applies constant pressure to the P6 point on your wrist.
NB: Acupressure is of course similar to acupuncture, but whereas acupuncture uses fine needles to stimulate the pressure points, acupressure relies on the pressure exerted by your (or your therapist's) fingers, or a device such as a wristband or bracelet.
Acupressure wristbands and bracelets are sold in packs of two and should always be used together, one on each wrist. All acupressure bands are drug-free and non-medicated. They are therefore completely free of side effect and can be used alongside motion sickness remedies, treatments and medications.