If you want to know what to prepare before getting into that Special Forces selection, it's better to read this list posted at Military Times... "Getting ready for Army Special Forces Assessment and Selection (SFAS), the first step to attending the Special Forces Qualification Course, requires commitment and a near life time of preparation. I recently spoke to a Special Forces operator and we discussed the top ten things a SF candidate needs to know before they take the SFAS challenge. He spoke of many different elements you should focus on during your training preparation. Here is the Top Ten List:"

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