Hi Bill, For a designer's perspective, try contacting Doug Bynum at Laser Alignment Inc. Email [log in to unmask] Phone 616-949-7430 x376. I met him during the CID exam last month and remember him saying he specifies CEM3 exclusively. Hope this helps. Sue James Taylor Company To: All I am looking for someone who has done the analysis on using FR4 vs CEM3 to get some advice.... I was reading about the CEM3 material and it said that it can be used in Multi-layer applications...? What are the advantages of going to CEM3 over FR4...? Can we get the same performance out of CEM3 that we would get from FR4 but for less money? What are the problems I need to be aware of in using CEM3? Do manufactures prefer one material over the other for ease of manufacture? Any help with this would be appreciated... Thanks in advance! Bill Brooks Senior PCB Designer - [log in to unmask] <mailto:[log in to unmask]> Co-Director / Education Officer / Webmaster for the San Diego Chapter of the IPC Designers Council http://www.ipc.org/SanDiego/index.html <http://www.ipc.org/SanDiego/index.html> Zoneworx, Inc. 40925 County Center Dr., Suite 200 Temecula, CA 92591-6037 Ph: 909.296.1226 (x1037) Fx: 909.296.1227 Visit us on the Web: zoneworx.com <http://www.zoneworx.com> ############################################################## 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 Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ##############################################################