Casella’s Campbell Stokes Sunshine Recorder is manufactured to a design based on British Meteorological Office (BMO) specifications. The sphere is made from well-annealed optical glass and the sunshine hours are recorded onto a card, which is inserted into the base of the unit. Each card is marked with hourly intervals and an optional transparent plastic template is also available to help measure the curved trace more accurately. The instrument is fully adjustable for operation at different geographical latitudes and leveling screws on the base ease installation. Two versions of the sunshine recorder are available, depending upon latitude.