Two types: 1) Standard type: with entry ports, most popularly used 2) Assembly type: ... galvanized steel entry panel, stainless steel clamps, entry ports, rubber boot and insert plug 2) Panel with 4" or 5" entry ports, types ... such as 1 port, 2, 3, 4, 6, 8, 9, 12, 16, 18, and ... 4) For extra port or holes, use port cap and insert plug, for airproofing 5) Suitable for all ...