One of the most powerful ways to increase muscle mass is to use different weights. This dumbbell kit from Marino comes with a variety of weight choices, ranging from 4.5 pounds to 44 pounds. To satisfy the training needs, you may change the weight by increasing or lowering the weight plates. It has a two in one design. The Adjustable Iron Dumbbells kit includes a binding rod that can be quickly transformed to a barbell in seconds to fulfil the maximum body exercise needs. Exercising at home or at the workplace saves time and resources. This dumbbell from Meerut Gym and Gymnastic Works is made of solid pure iron with a 7-layer electroplating procedure on the rim to prevent rusting. The connector handle is knurled for improved grip and exercise protection.