Saw this on HUKD.
There are a few different audio books of the same book that are paid. All have similar reviews and duration.
This book is the first and one of the most successful works on strategy and has had a huge influence on Eastern and Western military thinking, business tactics, and beyond. Sun Tzu was the first to recognise the importance of positioning in strategy and that position is affected both by objective conditions in the physical environment and the subjective opinions of competitive actors in that environment.
He taught that strategy was not planning in the sense of working through a to-do list, but rather that it requires quick and appropriate responses to changing conditions.
This book is public domain and you can download different versions of the book from LibreVok