The makers of the popular Fitbit activity tracker, have recalled their Fitness Force band. There have been reports of it causing an allergic reaction in some users. This reaction is most likely to be Allergic Contact Dermatitis. It is not clear why the reaction is occuring. It is thought it could either be the nickel it contains, or adhesives or materials used. Users that have been affected are able to get a refund for the band. You can read more about this in this CNN article
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