Actress Michelle Keegan endorsed a treatment priced at £2.50 in a national sale.
She called it as a 'godsend for holiday hair' in latest press coverage.
The promotion offers a £10 discount on the product, which has become popular among her fans.
Wales Online reported a £12.50 version of the mask renders damaged hair 'liquifying' after a single wash and earned enthusiastic reviews.
The Liverpool Echo called it 'one of the best ever', mirroring Keegan's endorsement.
The Mirror, Wales Online and Liverpool Echo all published stories on the price cut.
The discount has triggered strong web traffic.