This is the biggest hurdle.

Given the popularity of this keyword, counterfeit "hot" diodes are common. To ensure you receive genuine high-temperature parts:

Every diode has a maximum junction temperature (Tj). The standard NSFS160 might operate up to +125°C or +150°C. When engineers search for NSFS160 Hot, they are often looking for variants rated for High Temperature Operation—specifically, automotive or industrial grade devices that can survive +175°C junction temperatures.

If a circuit operates inside an engine bay, a downhole drilling tool, or a high-density server PSU, the ambient temperature alone might exceed 85°C. Using a standard diode here leads to thermal runaway. The "Hot" variant offers a lower thermal resistance (Theta JA) and a larger die pad to dissipate that internal heat.