The Procter & Gamble Company developed P&G Purifier of Water™ in conjunction with the Centers for Disease Control and Prevention (CDC). P&G™ sachets are now centrally produced in Pakistan, and sold to non-governmental organizations (NGOs) worldwide at a cost of 3.5 US cents per sachet. The P&G™ product is a small sachet containing powdered ferric sulfate (a flocculant) and calcium hypochlorite (a disinfectant). P&G™ was designed to reverse-engineer a water treatment plant, incorporating the multiple barrier processes of removal of particles and disinfection. To treat water with P&G™, users open the sachet, add the contents to an open bucket containing 10 liters of water, stir for 5 minutes, let the solids settle to the bottom of the bucket, strain the water through a cotton cloth into a second container, and wait 20 minutes for the hypochlorite to inactivate the microorganisms.