What is forged carbon?
Forged carbon is a composite material originally developed for aerospace and now used in Formula 1 cars, supercars, and high-performance equipment. Carbon fibre is kneaded into resin and pressed in a die at high temperature under extreme pressure. The process produces a material that is both extremely rigid and significantly lighter than stainless steel. The manufacturing process creates random marbled patterns in the material — each piece has a unique pattern that cannot be replicated. On the EFK-200XPB, both the case and the dial are forged carbon, so every watch has a one-of-a-kind appearance.
How does an automatic movement work?
An automatic (self-winding) movement uses a weighted rotor inside the case back that spins with the natural motion of your wrist. The rotor winds the mainspring, which stores energy and releases it through a gear train to move the hands. No battery is needed — the watch runs on mechanical energy. The EFK-200XPB also has manual winding: turn the crown to wind the mainspring directly when the watch has stopped or you want to top up the power reserve.
How long does the power reserve last?
Approximately 42 hours when fully wound. If you wear the watch daily, the motion of your wrist keeps it wound. If you take it off Friday evening, it will typically run through Sunday morning before stopping. To restart a stopped watch, wind the crown manually until resistance is felt, then set the time and date.
Is -20 to +40 seconds per day accurate?
This is normal accuracy for a mechanical watch in this class. Quartz watches are more accurate (±15 seconds per month), but mechanical watches offer something quartz cannot — a living, moving mechanism powered by physics rather than electronics. In practice, most well-maintained automatics settle within a narrower range. If precise timekeeping is critical, set the time weekly using the hacking function (pull the crown to stop the seconds hand for exact synchronisation).
What is the hacking function?
Hacking means the seconds hand stops when you pull the crown out to the time-setting position. This allows you to synchronise the watch to the exact second — set the minute hand, wait for your reference clock to reach the target second, then push the crown back in. Not all mechanical watches have this feature; the EFK-200XPB does.
What is the difference between sapphire crystal and mineral glass?
Sapphire crystal is rated 9 on the Mohs hardness scale (only diamond is harder); mineral glass is rated approximately 5–6. Sapphire resists scratches from keys, metal surfaces, and daily contact that would mark mineral glass. It also provides superior optical clarity — less distortion and sharper dial legibility. Most G-Shocks use mineral glass; the EDIFICE Automatic uses sapphire as a mark of its higher positioning.
Is this watch suitable for swimming?
Yes — 100-metre (10 BAR) water resistance handles swimming and recreational water activities. Avoid operating the crown underwater. Not rated for scuba diving.
What warranty does this watch come with?
The EFK-200XPB-1A comes with Casio's official warranty when purchased from City Chain Singapore, an authorised Casio retailer.