Kettlebell

Competition kettlebells are designed to by used with just one hand and the size and shape stays the same size regardless of the weight.

The advantage of these types of kettlebells is that your hand doesn’t slide around due to the limited space plus you can get used to the size even when the weight changes.

The main disadvantage is that they can only be used with one hand, so the all important two handed swing is out and so are the valuable goblet squats, halos, and many other beginner based exercises.