Sales and service facilities are available for refrigerators and freezers in Sacramento. Freezers are a more concentrated form of refrigeration, which is maintained below the freezing point of water. This is used for storing meats, ice, and other long-term storage items. These are insulated storage compartments that come with a heat pump. The pump transfers heat from the inside of the fridge to its external environment, keeping the interior of the fridge cool, so the foodstuffs do not spoil (it retards the growth of bateria due to the low temperature). Refrigerators are similar, except that they are maintained at a higher temperature. These can come as a combined unit, or be individually manufactured. A number of companies manufacture these items, varying in space, volume, finish, specifications, cooling ability, frosting or defrosting, and so on. Servicing facilities may also be made available in Sacramento as a part of the warranty or a maintenance package.