Filson canvas leather large field bag, shoulder strap messenger carry on travel luggage briefcase

Beautiful, barely used Filson leather trimmed bag - otter green weatherproof cotton canvas with leather trim.

This looks to me like the 'medium' style field bag, but with a zip around, larger dimensions. I don't know what this style is called.

The bag measures about 20" x 14" x 8" with buckle straps at the front, satchel style. Shoulder strap is about 25" drop at the longest. Please email if you need specific measurements, I'm not exactly sure how to properly measure this!