These Magnetic Bracelets ae ideal if you suffer from Sciatica, Arthritis, Rheumatoid Arthritis etc. The Magnetic Bracelets are made from Polypropylene Material which is Strong but Light & Comfortable & ONE SIZE FITS ALL with the adjustable straps. The Magnetic Bracelets are fitted with one STRONG 2000 Gauss Rare Earth Magnet. These magnets usually last a lifetime but the material may alter due to wear & tear over time. The penetration of these Magnets are one of the strongest on the market & we continue to get great results with this particular type of Magnetic Bracelet.