Fast Aid Advanced Relief-Xtra Magnetic Plasters Fast Aid Advanced Relief-Xtra Magnetic Plasters provide scientifically proven soothing relief with benefits usually noticed within 24 hours. Magnetic therapy is completely natural & has been used for thousands of years & these plasters create a magnetic force strength of 800 GAUSS to soothe the affected areas without drugs or chemicals. Fast Aid Advanced Relief-Xtra Magnetic Plasters are small, discreet ceramic magnets mounted on soft fabric plasters with hypoallergenic adhesive for easy application & are completely safe to use, even when wet.