Will likely need multiple applications
I ready review here an on UK Amazon before deciding to purchase.  I have dyed dark brown hair over likely medium to golden brown and grey hair (I'm 47).  I have weird/difficult multiracial hair that is coarse/curly and was different colors when I was younger.  (Dark brown on the back, more reddish on the top, with golden brown highlights.  I never liked the way my hair tended to turn red/brassy, so I tended to dye it a dark or ash brown.<br /><br />Wishing to embrace my natural grey or go gunmetal color, I decided to give this a try during our current lockdown period in the US.  This product would be best if shipped with shower cap, brush and gloves, as I had to go locate those items prior to use.  I made one batch and applied for 35 minutes.  I wasn't that shocked/impressed with the resulting color was uneven (bright towards the roots and then progressively darker) but this might be expected of my pattern of dark dye and pulling the dye through to the ends.  It did remove about 20% of the dye and lightened and variegated my hair overall.  I have dry, curly hair texture and this was very drying.  I followed up with Shea hair mask.  I plan to use this at least once more to see if I can get the grey strands to show before I seek professional help.  From the reviews, this seems to work best on naturally light colored hair for removing artificial/bright colors.
Rating: 3 stars