All Immersion Tins do not contain Bismuth! Bi causes problems with Lead Free Soldering and is not looked upon as an option for the future in some quarters. 100% Pure Tin systems are available that do not use an organic layer to prevent copper migration and therefore work successfully to stop whisker formation. The systems using organics cannot be controlled , and so if u do not have enough organic u do not know until the bd is in the field and failing with whisker growth. RG ############################################################## TechNet Mail List 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 web site (http://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or 847-509-9700 ext.5365 ##############################################################