The annealing condition is suitable for the processed products with the lowest strength after complete annealing. H machining hardening state is applicable to products that have improved their strength through machining hardening. The products may undergo (or may not undergo) additional heat treatment after machining hardening to reduce their strength. W solid melt heat treatment state (an unstable state) is only applicable to the alloy with natural aging at room temperature after solid solution heat treatment. This status code only means that the product is in the natural aging stage. T heat treatment state (different from F, O, H state) is suitable for heat treatment, after (or without) processing hardening to reach a stable product. The T symbol must be followed by one or more digits. The first digit after the T indicates the basic type of heat treatment (from 1 to 10), followed by the digits indicating a change in the details of the heat treatment. Such as the 6061 - T, 62; 5083 - H 343 etc. T1 -- cooled at molding temperature and aging to a generally stable state. T2 - annealed state (for castings only). T3 -- natural aging after solid solution treatment. T31 -- natural aging after solid solution treatment and cold treatment (1%),it can customized Aluminum Extrusion Enclosure, Device Box Case design etc.