Nano white is giving away FREE Dark Spot Corrective Serum at selected Guardian stores. Bring any empty serum bottle (except Nanowhite Serum) to these locations for an exchange of Nanowhite Dark Spot Corrective Serum 30ml and RM5 voucher. This exchange program is valid from 2 – 10 June 2018 only. For the first 25 participants at each location. Other terms and conditions apply.