1. Introduction
This manual provides instructions for the Timex Ironman Classic 50 Full Size Digital Watch, Model TW5K85900. This watch is designed for athletes and active individuals, offering a range of features for training and daily use. Please read this manual thoroughly to understand the watch's functions and ensure proper operation and care.

Image 1.1: Front view of the Timex Ironman Classic 50 Digital Watch. The watch features a black and grey resin case with a digital display and red accents on the buttons.
2. Key Features
- Adjustable Resin Strap: Black resin strap, 18mm wide, fits wrist circumferences up to 20 cm.
- 100-Hour Chronograph: Features a 50-lap memory for tracking multiple splits.
- Interval Training Timer: Multi-segment interval timer for structured workouts.
- 24-Hour Countdown Timer: Useful for various timing needs.
- 3 Customizable Alarms: Set alarms for specific times or events.
- 24-Hour Military Time Mode: Option for military time display.
- Dual Time Zones: Track time in two different locations simultaneously.
- Day, Date, and Month Calendar: Full calendar display.
- Durable Resin Case: 42mm black and grey resin case with an acrylic lens.
- Indiglo Night-Light: Illuminates the digital display for visibility in low light conditions.
- Water Resistance: Water-resistant up to 100 meters (330 feet), suitable for snorkeling and swimming, but not for scuba diving.
3. Initial Setup
3.1 Setting Time and Date
- Press and hold the SET button (usually top left) until the time display flashes.
- Use the START/SPLIT button (usually top right) to adjust the flashing digit (hours, minutes, seconds).
- Press the MODE button (usually bottom left) to cycle through hours, minutes, seconds, AM/PM, month, day, and year.
- Once all settings are correct, press the SET button again to exit the setting mode.
3.2 Activating Indiglo Night-Light
To activate the Indiglo night-light, press the INDIGLO button (usually top right or a dedicated button). The display will illuminate for a few seconds. This feature is useful in low-light conditions.
4. Operating Instructions
4.1 Chronograph Function
The chronograph measures elapsed time. To use:
- Press the MODE button until "CHRONO" or "STOPWATCH" appears on the display.
- Press START/SPLIT to begin timing.
- Press START/SPLIT again to record a lap/split time. The watch can store up to 50 lap times.
- Press STOP (usually bottom right) to pause the chronograph.
- Press RESET (usually top left) to clear the chronograph and lap memory.
4.2 Timer Function
The watch includes a 24-hour countdown timer and an interval timer.
- Countdown Timer: Navigate to the "TIMER" mode using the MODE button. Set the desired countdown duration using the SET and START/SPLIT buttons. Press START/SPLIT to begin.
- Interval Timer: This feature allows programming multiple timed segments for interval training. Refer to the detailed instructions in the full manual for advanced interval timer setup.
4.3 Alarm Function
The watch has three customizable alarms.
- Press the MODE button until "ALARM" appears.
- Use the SET button to select Alarm 1, 2, or 3.
- Adjust the alarm time using the START/SPLIT button and cycle through settings with the MODE button.
- Press SET to confirm and activate the alarm. An alarm icon will appear on the display when active.
5. Care and Maintenance
- Cleaning: Clean your watch with a soft, damp cloth. Avoid harsh chemicals or abrasive cleaners.
- Water Resistance: The watch is water-resistant to 100 meters. Do not press buttons underwater to maintain water resistance. Avoid exposing the watch to extreme temperature changes.
- Battery Replacement: The watch uses a lithium metal battery. When the battery is low, the display may dim or functions may become erratic. Battery replacement should be performed by a qualified technician to ensure water resistance is maintained.
- Storage: Store the watch in a cool, dry place away from direct sunlight and extreme temperatures.
6. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Display is blank or dim. | Low battery. | Replace the battery. Contact a service center for assistance. |
| Buttons are unresponsive. | Watch may be in a locked mode or internal issue. | Try a soft reset (refer to full manual if available). If issue persists, seek professional service. |
| Water inside the watch. | Water resistance compromised (e.g., buttons pressed underwater, seal damage). | Immediately take the watch to a service center. Do not attempt to open it yourself. |
| Incorrect time/date. | Time/date not set correctly or battery low. | Follow the "Setting Time and Date" instructions in Section 3.1. If it frequently resets, replace the battery. |
7. Specifications
- Model Number: TW5K85900
- ASIN: B00STN3PWA
- Case Material: Resin
- Case Dimensions: 42mm (diameter)
- Strap Material: Resin
- Strap Width: 18mm
- Water Resistance: 100 meters (330 feet)
- Display Type: Digital
- Battery: 1 Lithium Metal battery (included)
- Product Dimensions: 7.59 x 7.59 x 12.7 cm
- Item Weight: 45.36 grams
8. Warranty and Support
For warranty information and customer support, please refer to the official Timex website or contact their customer service department. Keep your purchase receipt as proof of purchase for warranty claims.
Online Support: www.timex.com/support.html





