4 in 1 Hammer, 9" has convenient interchangeable heads, which includes a steel, steel dome, nylon, and brass head. Why carry around 4 different hammers when you can save space and have only one? The different heads provide changeable hardness. The flat brass head on the hammer can be used for metal work, making and repairing jewelry and watches, shaping metals, Rounded face for peening and riveting. The brass head also helps prevent damage to objects and will not create sparks. The nylon head on the hammer can be used for unlimited surfaces. The separate black domed steel head is interchangeable and ideal for lessening marring of surfaces, riveting, sculpting, peening, flattening, shaping, fix dents in metal, and hammering chasing stakes. The separate black steel flat head is interchangeable and is great for use on a rounded and smooth surface to level it out. The flat head is used for flattening, shaping, bending, denting, hammering, and forming. It has a sturdy wood handle that is easy to grip.