【Solid Metal Weight & Protective Covers】Made of heavy-duty steel plates, this adjustable dumbbell weight boasts enhanced strength and durability. The protective polypropylene covers not only provide extra water resistance but also boost wear resistance, ensuring longevity and reliability. 【1 Hand, 1 Sec, 12 Weights】No more annoying weight loading or unloading with this adjustable dumbbell! You can switch between weights from 3 lb to 40 lb in mere seconds by effortlessly twisting the selectorized anti-slip handle with just one hand. The clear dials further enhance the ease of adjustment.