Introduction
This manual provides comprehensive instructions for the proper use and care of your Casio EFV-C120L-8AEF Analog-Digital Quartz Watch. Please read this manual thoroughly to ensure optimal performance and longevity of your timepiece. Keep this manual for future reference.
Product Overview
The Casio EFV-C120L-8AEF is an analog-digital combination watch designed for men, featuring a durable leather strap and a 10-year battery. It offers both traditional analog time display and versatile digital functions in a compact and streamlined design. The watch is built with a stainless steel case and mineral glass for durability.

Image: Front view of the Casio EFV-C120L-8AEF watch, showcasing its black dial, analog hands, digital display, and black leather strap.
Initial Setup
Setting Analog Time
- Pull the crown out to the first click position.
- Rotate the crown to adjust the analog hands to the correct time.
- Push the crown back in to the normal position to start timekeeping.
Setting Digital Time and Date
The digital display features various modes and settings. Refer to the button labels (typically A, B, C, D) on your watch for specific functions.
- In Timekeeping Mode, press the Mode button (usually bottom-left) to cycle through modes until you reach the Time Setting Mode (often indicated by flashing digits).
- Press the Adjust button (usually top-left) to select the digit or setting you wish to change (e.g., seconds, hour, minute, year, month, day).
- Use the Search/Light button (usually top-right) or Start/Stop button (usually bottom-right) to increase or decrease the flashing value.
- Repeat steps 2 and 3 until all desired settings (time, date, 12/24-hour format) are correctly set.
- Press the Adjust button again to exit the setting mode.
Operating Modes
Timekeeping Mode
This is the default mode, displaying the current time and date. The analog hands show the primary time, while the digital display can show time, date, or day of the week depending on the sub-mode.
Stopwatch Function
To use the stopwatch:
- Press the Mode button to navigate to the Stopwatch Mode.
- Press the Start/Stop button to start timing.
- Press the Start/Stop button again to stop timing.
- Press the Reset button (often the same as Adjust or Search/Light in Stopwatch Mode) to clear the stopwatch to zero.
Alarm Function
To set and activate an alarm:
- Press the Mode button to navigate to the Alarm Mode.
- Use the Adjust button to select the alarm time digits.
- Use the Search/Light or Start/Stop button to set the desired alarm time.
- Press Adjust to confirm and exit setting.
- Toggle the alarm ON/OFF using a designated button (refer to your watch's specific button layout).
Dual Time Mode
This mode allows you to view a second time zone.
- Press the Mode button to navigate to the Dual Time Mode.
- Use the Adjust and Search/Light buttons to set the desired second time zone.
Countdown Timer
To use the countdown timer:
- Press the Mode button to navigate to the Countdown Timer Mode.
- Use the Adjust and Search/Light buttons to set the desired countdown time.
- Press the Start/Stop button to begin the countdown.
Illumination
Press the Light button (often top-right or a dedicated button) to illuminate the digital display for better visibility in low-light conditions. Note that analog hands or small digital sub-dials may not be illuminated.
Care and Maintenance
Cleaning Your Watch
- Wipe the watch case and mineral glass with a soft, dry cloth to remove dirt and smudges.
- For the leather strap, wipe gently with a slightly damp cloth and allow it to air dry completely. Avoid excessive moisture.
- Do not use chemical cleaners, solvents, or abrasive materials, as these can damage the watch's finish and strap.
Water Resistance (100 Meters)
Your watch is water-resistant to 100 meters (10 ATM), making it suitable for swimming and snorkeling. However, it is not recommended for scuba diving. To maintain water resistance:
- Ensure the crown is fully pushed in before exposing the watch to water.
- Do not operate any buttons while the watch is submerged in water.
- Avoid exposing the watch to hot water or steam (e.g., showers, saunas), as this can compromise seals.
- If the watch is exposed to saltwater, rinse it thoroughly with fresh water and dry it with a soft cloth.
Battery Life and Replacement
The Casio EFV-C120L-8AEF is equipped with a 10-year battery. When the battery eventually runs low, it is recommended to have it replaced by an authorized Casio service center or a qualified watch technician to ensure proper sealing and functionality.
Leather Strap Care
To prolong the life of your leather strap:
- Avoid prolonged exposure to direct sunlight, extreme temperatures, and excessive moisture.
- Clean with a soft, slightly damp cloth as needed.
- Allow the strap to breathe; avoid storing it in airtight containers.
Troubleshooting
If you encounter issues with your watch, please refer to the following common problems and solutions:
- Analog Time is Incorrect: Pull out the crown and reset the analog hands as described in the "Setting Analog Time" section. Ensure the crown is fully pushed back in.
- Digital Display is Blank or Incorrect: Check if the battery is low (though it has a 10-year life, extreme cold can affect performance). Re-enter the Time Setting Mode to verify and adjust the digital time and date. If the issue persists, a battery replacement may be needed.
- Buttons are Unresponsive: Ensure the watch is not in a locked mode (if applicable). If the watch was recently exposed to water, ensure it is completely dry. If buttons remain unresponsive, contact a service center.
- Water Inside the Watch: Despite its water resistance, if you notice condensation or water inside the watch, immediately take it to an authorized service center. Do not attempt to open the watch yourself.
Product Specifications
| Model Number | EFV-C120L-8AEF |
| Display Type | Analog-Digital |
| Movement Type | Quartz |
| Power Source | Battery Powered (1 Lithium metal - included) |
| Battery Life | Approximately 10 years |
| Water Resistance Depth | 100 Meters (10 ATM) |
| Case Material | Stainless Steel |
| Case Diameter | 49.5 Millimeters |
| Case Thickness | 13 Millimeters |
| Dial Window Material | Mineral Glass |
| Band Material Type | Leather |
| Band Color | Black |
| Band Width | 5 Millimeters |
| Band Length | 20.5 Centimeters |
| Item Weight | 100 Grams |
| Manufacturer | Casio |
| Date First Available | May 15, 2024 |
Warranty and Support
Warranty Information
Your Casio EFV-C120L-8AEF watch comes with a 2-year limited warranty. This warranty covers manufacturing defects under normal use. Please retain your proof of purchase for warranty claims. The warranty does not cover damage resulting from misuse, accidents, unauthorized repairs, or normal wear and tear.
Customer Support
For technical assistance, warranty service, or inquiries about replacement parts, please contact your authorized Casio retailer or visit the official Casio website for service center locations and contact information in your region.