You are buying 10 wax pack empty slabs.  To seal these, you need a sonic welder or would have to glue them shut.  We will offer a service to seal these for buyers for $3.00 a slab plus shipping on the welder.  Message me for costs on this and I will create private listings if interested (depending on quantity).  Otherwise, you would need to glue them shut.  As an FYI - These holders only hold tightly packed wax packs such as all of the 1980's Topps wax packs.