This Seiko 5 model SSK023K was designed and constructed to be reliable, robust, and functional encompassing the Seiko 5 Sports characteristics in a slimmer and versatile design. With the additional GMT function, it allows you to also track a secondary time zone. A handsome timepiece that has a balanced blend of function, specs, and style. - Cal. 4R34- 39.4mm Case Size - Screw See-Through Case Back - Three-Fold clasp w/ secure lock, push button release- 100 Meters Water Resistant