Safari hats have three very important functions to perform so if you are looking to get one make sure that it does the three things below very well.
These facts were compiled from the online travel journal recommendations of previous African travellers at African Safari Journals and my own personal wildlife experiences.
#1: Provide complete coverage from the sun.
It should provide all round shielding especially in the back of the neck area which is where a lot of them come up short. The African sun has the ability to burn even when it's low on the horizon.
#2: Should allow your head to "breathe".
On a hot day in Africa you will feel even hotter if body heat is trapped on your head.
It should be gas permeable so that the heat generated can escape and allow you to cool off.
#3: Must be water absorbent on the inside and waterproof on the outside.
Getting sweat in your eyes is no way to spend a day spotting wildlife. It should absorb any sweat before it gets to go anywhere.
Rain in Africa tends to be a fast and furious affair so if you get caught without cover it must be waterproof to effectively protect you from the deluge.
You are going to have limited space in your luggage on an African trip so a big advantage is if you can flat pack your safari hat (it's crushable), giving you more space for other items and ensuring it comes out of your suitcase in wearable condition.
Something that's not essential but much more convenient when the wind blows or when you are travelling in an open vehicle is a wind cord or cinch strap. You'll be glad to have it when others are chasing down their headgear after a sudden gust or having to constantly hold it to prevent it from lifting off.
It goes without saying that your headgear should be comfortable because you are going to be wearing it a lot on your trip. Keep in mind that dust is omnipresent in Africa so something that is easy to keep clean is a bonus.
Tilley Endurables are some of the best you will find anywhere in the world bar none. The LTM6 and T3 models are particularly well suited as they conform to all the requirements above.
I've had one of the Tilley safari hats for a number of years now and it's served me very well. It's guaranteed for life and even insured against loss.