The electric fence I purchased was actually called "poultry fencing". Another good thing about it, it's very easy to move/relocate.
It is a plastic coated wire fencing, go online and request a catalog from them,(Kencove) they have lots of different kinds of electric fencing.
It has both horizontal and vertical wires, some are hot, some are not. It costs about $160.00 for enough to do a 40' sq. pen.
One of our Brittany bird dogs got loose, run up to the fence, didn't even hit it, but sensed it I guess, and took off. Another dog we have a little terrier, actually ran up and stuck his nose to the fence, he yelped and now he will not go withing 100 ft. of the chicken pen.
Yes, hawks could still get the chickens, but that's why I put up with a couple of roosters. My older roo, he signals everyone to get inside the hen house if he sees anything flying and approaching the pen. He even runs everyone in if he sees geese flying at a distance. It is really something to see, how he guards the girls. He does a clicking noise, and in they go.
DonnaBelle