9105.19.10 - Not constructed or designed to operate for over 47 hours without rewinding

This HTS category, 9105.19.10, specifically covers alarm clocks whose mechanical movements are not designed or constructed to operate for more than 47 hours without requiring rewinding. These are typically smaller, more basic alarm clocks where manual winding is a frequent necessity. The focus here is on the operational duration of the clock's internal mechanism.

The key differentiator for this subcategory lies in its limitation regarding operational time between windings. Its sibling category, 9105.19.90, encompasses alarm clocks with movements designed to operate for over 47 hours without rewinding, signifying a greater complexity or power reserve in their mechanism. Therefore, the distinction is purely based on the intended operational autonomy of the movement.

As a leaf node in the HTS classification, this category does not have further subcategories. Classification into 9105.19.10 is definitive once the item is identified as an alarm clock with a movement measuring not over 50 mm in width or diameter, and critically, not designed to operate for over 47 hours without rewinding. Practical examples might include many battery-operated or small spring-wound travel alarm clocks.