Casio G-SHOCK Men's Solar Watch with Bluetooth, G-STEEL Small Model Men's Rubber Band GST-B400-1AJFProduct Highlights strong> Achieving further miniaturization of components and slimming down the module. While maintaining high functionality with Bluetooth and solar power, power consumption has been significantly reduced. Additionally, the Carbon Core Guard structure maintains impact resistance while achieving the thinnest profile in the G STEEL series (as of December 2020). From the back to the top of the bezel, it measures 12. 9mm, over 1mm