Bags

The main difference is that liters (L) measure the actual internal volume (the capacity) of a bag, whereas size is a classification (e.g., S, M, L) used by certain top brands, like The North Face, to categorize this capacity. For instance, a Small size typically corresponds to ~50L, while a Medium corresponds to ~71L.

For a week-long trip, the Medium (M) size of The North Face Base Camp Duffel, which offers a capacity of 71-90 liters, is the ideal choice. It provides the perfect balance between generous interior storage space and ease of transport.