Polystyrene is an .060 thick material that Howmac laminates to gatorfoam, high density foam or E.P.S. foam (beaded foam). The combination of the styrene and the foam is what HowMac calls a “Permaletter”.
Styrene provides a smooth surface for the face of the Permaletter that can be painted a matching or contrasting color to the edge.
When an extra thick letter (HowMac can cut up to 10” thick) is required with a custom colored face, the Permaletter is the answer. Permaletters are not recommended for exterior use.