Don't confuse "tenting" with "plugging". Solder mask tented vias may not necessarily "close" the via opening. Tenting really means the pads are tented...solder mask may fill the hole, but only smaller ones. Plugging is a better process for vias under components. Plugging is best performed on both sides; however, the process your board shop uses needs to be exact...otherwise, moisture, contaminates, etc may become entrapped causing a major mess during assembly... As for the sodler mask, Enthone, Coates, are probably the most common and they will do the job quite nice... Franklin --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 -----------------------------------------------------