This Seiko 5 Sports model SRPD85K, with a calibre 4R36 automatic movement has the same movement found in man of Seiko’s high-end models. With 24 jewels and a whopping 21,600 beats per hour that allows for a vigorous 40-hour power reserve. This timepiece is an example of Seiko’s unique ability to combine design, fashion, and reliable materials in a watch. - Calibre 4R36 - Automatic Movement with manual winding - 42.5mm Case Size - 13.4mm Thickness - Stainless Steel Case - Nylon Strap - 41 Hours Power Reserve - Hardlex Crystal - See-through Case Back - Screw Case Back - Unidirectional Rotating Bezel - 100 Meters Water Resistance - Day and Date Display