The Longines HydroConquest watch model # L37823989 features: stainless steel pvd coated case, blue rubber strap with a folding clasp / buckle. It has a blue dial, uni-directional bezel. The case size is 43mm. This automatic watch is powered by the caliber L888 is a 25200 VPH movement and has a power reserve of 72 hours . The Longines L37823989 uses a sapphire .