3.      There are various kinds of flexible eva bag sically, there are two kinds -- open package and closed waterproof bag, xible packages that are thoroughly sealed and can stand stresses at the edges of heat seal are closed packages, like middle-sealed bags, four-edge sealed bags, and self-supporting eags eva bag. A circular hole which would be sealed after the insertion of puffing probe must be opened at the center of waterproof bag The position of circular clear bag effect theresult of test, and we suggest the opening position at the center of specimen. Three side seal eva bag, hand bag and shopping bag, etc. belong to the category of open package. We can only test the seal characters of materials and the three sides except the unsealed one with specially made accessories. For example, the LSSD-01P Leak and Seal Strength Detector of Labthink with different position from that of closed package. Of course, users can implement sealability test of heat seal edges of open waterproof bag sing LSSD-01P and LSSD-01R restraining plates http://www.niceindustry.com/product_.asp