Introduction
This instruction manual provides essential information for the proper use and care of your Casio MRW-210H-7AVCF analog watch. Please read this manual thoroughly to ensure correct operation and to maximize the lifespan of your timepiece. This watch features a sporty design, 100-meter water resistance, a date display, and a rotary bezel.
Setup
Setting the Time
- Pull the crown out to the second click position. The second hand will stop.
- Rotate the crown to advance the hour and minute hands to the desired time. Pay attention to AM/PM. The date display will change when the time passes midnight.
- Push the crown back in to the normal position. The second hand will resume movement.
Note: To ensure correct AM/PM setting, advance the time past 12 o'clock. If the date changes, it is midnight (AM). If the date does not change, it is noon (PM).
Setting the Date and Day
- Pull the crown out to the first click position.
- Rotate the crown clockwise to set the day.
- Rotate the crown counter-clockwise to set the date.
- Push the crown back in to the normal position.
Important: Avoid setting the date and day between 9:00 PM and 4:00 AM, as this may interfere with the automatic date change mechanism. If you need to set the date during this period, first change the time to outside this range, then set the date, and finally reset the time.
The day display includes multiple languages. Continue rotating the crown until the desired language appears.

Image: Front view of the Casio MRW-210H-7AVCF watch, highlighting the watch face, hands, date and day display, and the crown on the right side.
Operating the Watch
Using the Rotary Bezel
The watch features a bi-directional rotary bezel. This bezel can be rotated to mark elapsed time. Align the triangle marker on the bezel with the minute hand at the start of an event. As time passes, the minute hand will indicate the elapsed time against the bezel's markings.
Water Resistance
This watch is rated for 100-meter (330 feet) water resistance. This means it is suitable for swimming and snorkeling. However, it is not suitable for scuba diving. Do not operate the crown or any buttons while the watch is wet or submerged in water.

Image: The Casio MRW-210H-7AVCF watch displayed on a wrist, illustrating its size and fit.
Maintenance
Battery Replacement
The watch is powered by one SR927SW lithium metal battery, which is included. The approximate battery life is 3 years. When the watch stops or the hands move erratically, it is time to replace the battery. Battery replacement should be performed by a qualified watch technician to ensure proper sealing and water resistance.
Cleaning
Wipe the watch case and band with a soft, dry cloth to remove dirt and moisture. For the resin band, you can use a mild soap solution and rinse thoroughly with fresh water, then dry completely. Avoid using harsh chemicals or abrasive cleaners.
Water Resistance Precautions
- Ensure the crown is fully pushed in before exposing the watch to water.
- Do not operate the crown or any buttons while the watch is submerged or wet.
- Avoid exposing the watch to hot water, steam, or extreme temperature changes, as this can compromise the water resistance seals.
- Have the water resistance seals checked periodically by a professional, especially after battery replacement.
Troubleshooting
Incorrect Day or Date Display
If the day or date display is incorrect, refer to the "Setting the Date and Day" section. Ensure you are setting the time correctly with respect to AM/PM, as this affects the automatic date change. If the date changes at noon instead of midnight, you have set the time incorrectly by 12 hours. Adjust the time by advancing the hour hand by 12 hours.
Watch Not Keeping Accurate Time
The watch has an accuracy of approximately ±20 seconds per month. If the watch is significantly inaccurate, it may indicate a low battery or a need for servicing. Replace the battery if it's nearing its expected lifespan. If the issue persists, consult a qualified watch technician.
Specifications
- Model Number: MRW-210H-7AV
- Movement: Quartz
- Display: Analog (Hour, Minute, Second hands)
- Date Display: Day and Date
- Water Resistance: 100 meters (330 feet)
- Case/Bezel Material: Resin
- Band Material: Resin
- Glass: Resin Glass
- Case Diameter: 53.1mm
- Accuracy: ±20 seconds per month
- Battery Type: SR927SW (1 Lithium Metal battery)
- Approximate Battery Life: 3 years
- Product Dimensions: 4.2 x 3.3 x 2.2 inches; 3.88 ounces

Image: A visual guide comparing various watch case diameters, illustrating the relative size of different watches.
Warranty and Support
Your Casio watch comes with a manufacturer's warranty. Please refer to the warranty card included with your purchase for specific terms and conditions, including warranty period and coverage details. For further assistance, product information, or service inquiries, please visit the official Casio website or contact Casio customer support.
For more information, you may visit the Casio Store on Amazon.

Image: The retail packaging box for a Casio watch, typically containing the watch, manual, and warranty information.





