Home Depot is labelling green products so that customers can quickly and easily recognise the environmentally friendly items in the range by means of appropriate labels. For classification purposes the products must fit into one of the system's five categories: clean air, water conservation, energy conservation, healthy living or sustainable forestry. According to Home Depot, over 2 500 products are suitable for inclusion in its Eco Options programme. They range from natural insect repellents, cellulose insulating materials and front-loading washing machines, through to organic fertilisers and energy-saving light bulbs and on to programmable thermostats and certified timber.