About the Kirk-ook: The base reflector is slotted through the rear reflector to provide more stability for the cooker in windy conditions (with less base material extended and more base material supported). The bottom-rear of the cooker can be supported with rocks as shown in the picture. By extending the sides you will create a wave-formed ripple focusing more rays in the center for higher effectiveness (depending on the angle of the sun). Higher temperatures can be reached using a turkey bag around the pot & lid or split and covering the Kirk-ook on windy days (alleviating the effect from high winds known as wind chill) . The plastic film can be coated with UV agents to avoid discoloration and distortion. Alternate transparent plastics are being tested for higher heat resistance (*email