Aluminum-clad fused silica columns offer the same inert internal fused silica surface, but with an outer layer of aluminum instead of the standard polyimide normally found on GC capillary columns

The 400-1HT phase is similar to our non-polar 007-1 dimethylpolysiloxane phase, which separates compounds according to boiling point, but 400-1HT columns are produced on 0.23mm ID aluminum-clad fused silica.  This allows for higher operating temperatures compared to the standard polyimide-clad fused silica columns.