There is no doubt that our product is energy-saving because it can dim after three seconds automatically. And it has HD-compatible, which you can see the digital clearly. Design of the carabiner buckle, our product is safe and firm to use. Certainly, our product can be fixed on your belt or bag tightly without falling so that is safe to use.It is made from metal, is durable and safe to use. The length of the product is 7.5 cm, the width is 3.9 cm and the thickness is 1.1 cm.The watch suitable for multiple scenarios. Item Name: Sport Watches Material: Metal Features: Luminous, Energy-saving, Anti-oxidation Movement: Electronic Movement Color: Black,Red Size Details: 7.5cm x 3.9cm x 1.1cm/2.95" x 1.54" x 0.43" (Approx.) Notes:Due to the light and screen setting difference, the item's color may be slightly different from the pictures.Please allow slight dimension difference due to different manual measurement.Package Includes:1 x Sport Watches