The In2Mix refills can be kept for 1 year at room temperature or in an airconditioned room (73°F/23°C). To keep the refill sachets for 2 years, store them in the fridge. Always use a cooler bag in the field and in the vehicle to keep the sachet temperature below 110°F/43°C all the time (melting point larvicide). If you have sachets left after a warm day in the field, you can use them again if stored properly during transportation and overnight. Don’t worry if the shipment from your distributor arrives a little warm. Just place them in the fridge immediately, they are still effective if they remained below 110°F/43°C.