Thanks to BobInFla for sharing the link above for the manual for the AT Pro. I take no credit for supplying the link I mearly wanted to perhaps make it a little easier to find once you arrive at the page its not real difficult but for anyone that may have trouble maybe this will help.
Once you arrive on the Garrett Home Page click on the tab "Hobby Divison" which will take you to the next page.
On the next page at the top of the page click on the tab "Warranty/Support" (2nd tab from the LH side) and select the obvious "Manuals" this will also direct you to the next page where you find the manual you were looking for!
Again, I take no credit for supplying the link credit goes to BobInFla for that. I was only tring to help someone that may have had to study a second on where to go from there Of coarse I may be the only one that had that brain fart for a second