Which kind of fox are you going to be trapping,reds,greys,or both? Traps,#1-1/2 to #1-3/4 would be plenty good for fox,but if you have coyotes around,i wouldn't use anything less than a laminated #1-3/4 and preferably a good #3 in case of a coyote hitting your set. For grey fox,i like the flat set,using dried dog food.You want to blend the set in natural looking as the ground looked before you started.Yep,i said dried dog food.You would have to test dog food and see which one they like before the season starts,if you decided to use it.All you do is sprinkle it in a foot and a half circle over and around your trap.[Never use fox urin on a dog food set.]In dirt holes,grey fox can be caught on a variety of stuff.I've caught them on peppermint candy,almond extract,gland lure,food baits,and a variety of other stuff.Red fox won't touch a lot of things a grey will.For reds,i like the dirt hole set and use gland lure and food baits.[One of the best baits for both grey and reds is tainted mice.]If you can get it,Hawbakers makes good gland lures and food baits for both red and grey fox.Remember,it's a good idea to spray some red fox urin around your set after your finished,this helps cover the human odor and tells a fox another fox was there.