is a Hyundai/Kia specification for automatic transmission fluid (ATF) used in their 6-speed automatic transmissions (specifically the A6MF1, A6MF2, etc.). It is a low-viscosity fluid.
The "2" in HCF-2 is the most important part of the label. Honda’s first-generation CVT fluid (often just called ) is not compatible with HCF-2. hcf-2 equivalent