OG team has successfully carried out an exterior wall cleaning work for Parkview Hong Kong. The cleaning chemical is using OG Restorer Special. Merits of this project include: first is the reduction of cleaning working time by as much as 50 percent from conventional cleaning method, and second is eliminating the use of high pressure water spray gun. The above merits are due to the use of OG Restorer, which is particular effective in removing stains on tile surfaces without any need of mechanical action, stains are self rinse off once applied.