Rubber kettlebells perform as well as cast iron ones do, but they have a rubber coating that protects your floors and silences their impact when they hit the floor. They also prevent noise and vibration, making them a solid alternative for home gyms, studios, or anywhere else where floor protection is essential. It can also aid storage and holdout of items on the surface. Rubber kettlebells provide the same functional-exercise benefits of their iron counterparts, but they are heavier-duty and wonβt scuff floors.