Daan I don't think the storage at -50 deg. does harm your equipment too much. Just be sure it is sealed in dry gas or vacuum. I have one thought: Tin has a transition temperature of +13 deg. from tetragonal ( metallic tin ) to cubic (tinpest). This effect is very slow, but if one is storing electronic equipment for years at low temperatures it might at least have a cosmetic effect on the solder joints. And if the PCB's are coated ( as usual in military applications ) this will look really ugly. Best regards Guenter Grossmann Swiss Federal Institute for Materials Testing and Research Center for Reliability Duebendorf Switzerland ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################