high strength extract standardised at 3% rosavins, correct dose & species of rhodiola, perfect partner to siberian ginseng, magasorb & theanine, excellent value for uk-made taste free, coated tabletsnature’s best rhodiola is a premium, high strength extract equivalent to 500mg of dried rhodiola rosea, obtained from the rhizome & root of the herb. standardised to ensure that it contains exactly what the label states, 2 tablets provides a guaranteed 3.75mg (3%) of precious rosavins, the ‘active’ compounds found in the herb & referred to in studies. in the course of developing our product we tested a number of raw materials available & determined that the few claiming to contain higher percentages than 3% often did not. the raw material we use is specifically tested for its rosavin level & reassuringly, we screen all herbal materials to ensure none have been irradiated. rhodiola rosea has been used for centuries & it makes the perfect partner to siberian ginseng, magasorb® & our theanine/lemon balm supplement!