This is the system we used.
http://store.petsafe.net/deluxe-in-grou ... nce-systemWe put their collars on in the morning and they stay outside a all day. We bring our cats in at night and take the collars off. I do wish the transmitters were smaller, but our cats quickly got used to them. They each got shocked twice at first, but the collars emit a very low beeping noise when they get close to the fence, and they very quickly learned what the beeping meant. It's simple to set up. We have the transmitter unit inside the house and drilled the wires to the outside. We attached the wire to our fence through eye hooks. Most important - run the wire on the bottom one direction then loop back on the top of the fence - this is the best way to contain a cat. Nothing is 100% foolproof and you'll have to see how it works with your very persistent cat. But we have two bengals effectively contained and believe it's the best thing we ever did for them.