Dear Sir/Madam,
ALUMINUM FRAME:
Anodizing Type III the ISO standard for it MIL-A-8625(Type III) - it should be temperature about 0 degree. The current should be about 30-40 Amps. And the time from 90 to 120 minutes.
Surface treatment: Hard Anodized. it is with sandblasting 120# first, then hard anodize(20-25μm)
Color will be dark grey (olive) or black