8411.81 - Of a power not exceeding 5,000 kW:

HTS code 8411.81 encompasses gas turbines and their parts that generate a power output not exceeding 5,000 kilowatts (kW). This classification is specifically for turbines operating within this lower power range, distinguishing them from more powerful units. These turbines are integral components in various industrial and transportation applications where substantial but not the highest levels of power are required.

This category is differentiated from its sibling, 8411.82, solely by the power output. While both deal with "Other gas turbines," 8411.81 is exclusively for those with a maximum power rating up to 5,000 kW. This power threshold is a critical factor in the classification, indicating different operational scales and potential uses.

Within HTS code 8411.81, further subdivisions exist to refine classification based on specific applications. Subcategory 8411.81.40.00 covers "Aircraft turbines," identifying gas turbines designed for aeronautical use and often subject to specific aviation regulations. The remaining turbines within this power range fall under the broader category of "Other" (8411.81.80), which would include industrial turbines used for power generation, mechanical drive, or other non-aircraft applications.