Fore Hock is the whole front leg of the pig,
It can be divided into two.
The lower part of the Fore Hock is called Prime Hock. It will weigh about 1 1/3 pounds (600g), and should be braised.
The upper part is called the Hock Knuckle. It has lots of bone in it, and weighs about 3 1/3 pounds (1.5 kg..) It can be boned, rolled and called a picnic ham (UK), or meat can be removed from the bones and used in chunks in dishes, etc.