Kettlebells are very simple but effective home gym equipment that are very effective in improving core strength and stability and are increasingly popular in CrossFit and circuit training. The Ironman Pro 4kg Cast Iron Coated Kettlebell features a flat bottom for stability, a large comfortable handle for a secure grip, a corrosion-resistant hammer-tone finish that increases durability and are marked with both the imperial and metric weight. Kettlebells can be used in a wide variety of ways to exercise making them ideal for home fitness workouts. They can be held in different ways to vary exercises and you can even use them as a handle for uneven push-ups.