The Jin Hung Aluminium Heart Bar shoes are drop forged from high quality aluminium then heat-treated by a special process to T6 hardness. These shoes can be easily altered cold, but for radical re-shaping or forging clips, heat gently in a gas forge or hot water. Heating the shoe will cause it to lose its hardness. This can be partly restored by reheating the shoe after shaping and quenching it in cold water.
The bar shoes were made in a lighter, narrower section with a broader toe to minimize shaping.