Read more Automatic Self Winding Watch --- Explorer Series • There are many planetary trajectories on the dial. The metal luminous scales like many asteroids. It's dotted on the brushed dial and feels the vast universe slowly turning between the wrist. • Japanese Automatic Self-wind Movement: It functions without any battery. It will get enough power by wrist shaking to keep accurate time and calendar work. Read more Features --- Luminous and 50M Water Resistant • Luminous hands give you a little light in the dark so that you can see the time at night. It used the fluorescent powder which need absorb enough high light before they can glow in the dark. • Waterproof Watch: It's okay for sweating, hand wash, rain day, and withstands splashes. But not suitable for swimming and diving. Read more Material 1.Case Material: Stainless steel 2.Band Material: Stainless steel 3.Dial Window: Synthetic sapphire 4.Display Type: Analog Durable with Comfort 1.Band Width: 20mm; Band Length: 220mm 2.If the band length is too long, you can use our small tool which in the box to disassemble several steel strips to fit your wrist size Best Gift Idea Carefully prepared, packaged and delivered to you in our exquisite gift box. Best choice for Valentine’s Day, Father's Day, Birthday and other meaningful day with big surprise. Fantastic present for friends and family. Read more Case size 40mm 40mm 40mm 40mm 40mm Case thickness 10.3mm 10.3mm 10.5mm 6mm 10.3mm Glass Synthetic Sapphire Synthetic Sapphire Synthetic Sapphire Synthetic Sapphire Synthetic Sapphire Movement Japanese Automatic Self-Wind Japanese Automatic Self-Wind Japanese Automatic Self-Wind Japanese Quartz Japanese Automatic Self-Wind Battery × × × √ × Water Resistant 5ATM 5ATM 5ATM 5ATM 3ATM