HMI facings are chosen with different purposes in mind

Maritex.
An immensely tough fibreglass cloth with a sealed metallised skin so it cannot absorb oil. It won’t tear or fray. It looks heavy duty, and it is fire zero rated. Maritex is simply the best facing in the HMI range.

Maritex is fire zero rated to BS 476 parts 6 and 7.

Sealglass.
A tough off-white glass cloth, sealed against oil. The cloth is extremely tough and will not tear. The sealant will burn off in a fire. The material meets the ISO 9094 fire requirements of the EU Recreational Craft Directive.

Re-inforced silver polyester.
This facing meets the requirements of the Recreational Craft Directive. It provides a seal to keep oil out. You can pierce it, but it has a re-inforcing layer behind it. It will burn, but once laminated in place it meets the ISO 9094 fire requirements of the EU Recreational Craft Directive. In a fire the facing will burn, but not the foam behind it.