Introduction
This manual provides comprehensive instructions for the Timex TX 770 Series FLY-BACK Chronograph T3B851 watch. Please read this manual carefully to understand the features and proper operation of your timepiece. This watch combines classic design with advanced chronograph functionality, powered by a precise quartz movement.
The Timex TX 770 Series FLY-BACK Chronograph T3B851 features a durable stainless steel case and bracelet, a black dial, and a sapphire crystal for enhanced scratch resistance. Its chronograph function includes a fly-back feature, allowing for quick resetting and restarting of the stopwatch with a single press.

Image: Front view of the Timex TX 770 Series FLY-BACK Chronograph T3B851 watch, showcasing its black dial, silver hands, and stainless steel bracelet.
Setup
Setting the Time
- Pull the crown (the knob on the side of the watch) out to the furthest position.
- Turn the crown clockwise or counter-clockwise to set the hour and minute hands to the correct time.
- Push the crown back in to its original position to start the watch.
Adjusting the Bracelet
The stainless steel bracelet can be adjusted for a comfortable fit. It is recommended to have a professional jeweler adjust the bracelet by adding or removing links. Improper adjustment can damage the bracelet or the watch.
Operating the Chronograph
The TX 770 Series features a FLY-BACK chronograph, which allows for precise timing of events.
Basic Chronograph Operation
- Start: Press the top pusher (button) to start the chronograph. The chronograph second hand will begin to move.
- Stop: Press the top pusher again to stop the chronograph. The elapsed time will be displayed.
- Reset: After stopping the chronograph, press the bottom pusher to reset all chronograph hands to their zero positions.
Fly-Back Function
The fly-back function allows for immediate resetting and restarting of the chronograph with a single press, useful for timing consecutive events.
- While the chronograph is running, press the bottom pusher.
- The chronograph hands will instantly reset to zero and immediately begin timing again from zero.
Maintenance
Cleaning
To maintain the appearance of your watch, wipe the case and bracelet regularly with a soft, dry cloth. For stainless steel, a slightly damp cloth can be used, followed by a dry cloth. Avoid using harsh chemicals or abrasive materials.
Water Resistance
While your watch may be water-resistant, it is important to avoid exposing it to hot water, steam, or chemicals, which can compromise the seals. Always ensure the crown is fully pushed in before any contact with water.
Battery Replacement
The watch is powered by a quartz movement and requires a battery. When the battery runs low, the watch may stop or the second hand may jump in irregular intervals. It is recommended to have the battery replaced by an authorized Timex service center or a qualified watchmaker to ensure proper sealing and functionality.
Troubleshooting
Watch Not Running
- Check if the crown is fully pushed in.
- The battery may need replacement. Consult a professional watchmaker.
Chronograph Hands Not Resetting to Zero
- If the chronograph hands do not align to the zero position after resetting, consult the Timex service center for adjustment.
Specifications
| Feature | Detail |
|---|---|
| Brand | Timex |
| Model Name | T3B851 |
| Item Model Number | T3B851 |
| Movement Type | Quartz |
| Display Type | Chronograph |
| Special Features | Chronograph |
| Case Material | Stainless Steel |
| Case Diameter | 44 Millimeters |
| Case Thickness | 10 Millimeters |
| Crystal Material | Sapphire Glass |
| Band Material | Stainless Steel |
| Band Type | Bracelet |
| Band Width | 20 Millimeters |
| Band Color | Black |
| Dial Color | Black |
| Clasp Type | Deployment Clasp |
| Item Shape | Round |
| Dial Style | Sporty |
| Included Components | Bracelet |
| Manufacturer | TX Uhren |
| UPC | 753048192564 |
Watch Size Guide

Image: A visual guide illustrating various watch case diameters, ranging from 14-16mm up to 50-54mm, to help understand watch sizing. The Timex TX 770 Series has a 44mm case diameter.
Warranty and Support
Warranty Information
Regardless of your legal right of withdrawal, you have a 30-day return right for many products. For exceptions and conditions, please refer to the specific terms provided at the point of purchase or on the retailer's website.
Customer Support
For further assistance, technical support, or warranty claims, please contact Timex customer service or visit the official Timex website. Keep your purchase receipt as proof of purchase.





