Size Approximately 38 x 38 x 11 mm Windshield Hardlex Crystal Glass Material Stainless steel 21 jewels automatic day-date calendar Lumibrite (hand index) 30 meters daily life waterproof Back cover skeleton Weight 115 grams Detailed explanation of instruction manual is Warranty It will be a PDF file from the URL written on the card. There are models of Seiko 5 automatic watches that do not wind the mainspring even when the crown is turned. This model does not have manual winding function. The mainspring will be automatically wound by attaching it to your arm and moving it. You can see the rotor turning from the skeleton part on the back. Before putting it on your wrist, you need to hold the watch in your hand and shake it well to charge it. Caution when adjusting the calendar: Please do not adjust the calendar between 9:00 pm and 3:00 am. Doing so may put stress on the watch mechanism and cause it to malfunction. Always adjust the time by advancing the time clockwise. If the time is between 9:00 pm and 3:00 am, turn the crown clockwise until it reaches the 3:00 position, then adjust the calendar. Do not leave the calendar display at a halfway position. For details, please see the instruction manual in the PDF file from the URL listed on the Warranty Card.