At WeCare . our goal is to provide you with the highest quality training equipment so you can focus on your training. Rubber-coated dumbbells are designed for indoor use . so we recommend keeping them out of direct sunlight. The rubber coating is safe . flexible . stretchy . and waterproof. When new they can smell of rubber and may have some residue . but that will go away after a few uses or when wiped down with soapy water. With minimal storage space required . these dumbbells are perfect for training at your home . office . or gym. The hexagonal design ensures our dumbbells will stay where you place them . reducing the risk of accidents or damage to the floor. Free weight workouts improve strength and stamina while helping you burn fat and tone your body.