... freshness of preserved food. Application: D type series air cooler is classified in accordance with the ... storage temperature. DL type of high temperature, fin space 4.5mm, is applicable for cold storage above ... fruits and eggs; DD type of moderate temperature, fin space 6.0mm, for cold storage around -18 ºC ... aquatic products; DJ type of low temperature, fin space 9.0mm, for -2ºCcold storage, used for ...