1. Introduction
The Callez C500QRJ45 RJ45 Telephone Headset is designed for clear and natural communication in professional environments. Featuring a noise-cancelling microphone and a quick-disconnect (QD) cord, this mono headset offers comfort and convenience for extended use with compatible landline phones.

This manual provides detailed instructions for setting up, operating, and maintaining your headset to ensure optimal performance.
2. Package Contents
Verify that all items are present in your package:
- Callez C500QRJ45 Headset
- Quick Disconnect (QD) to RJ45 Cable
- RJ45 to RJ9 Headset Adapter (if included as a free gift)

3. Compatibility
This headset is designed for specific landline phone models equipped with an RJ45-8P4C headset jack. It is NOT compatible with smartphones, computers, or phones with an RJ9-4P4C headset jack unless using the provided adapter.
Compatible Landline Phone Models (RJ45-8P4C Jack):
- Mitel/Aastra: 5370 IP, 5380 IP, 6865i, 6867i, 6869i, 6771, 6773 IP, 6775 IP, 7434 IP, 7444 IP
- Siemens/Unify: OpenStage 30 (T/G), OpenStage 40 (T/G), OpenStage 60 (T/G), OpenStage 80 (T/G), Unify OpenScape CP200, CP205, CP400, CP600, CP600E, IP 35G Eco, IP 55G
- Innovaphone: IP230, IP240, IP241
Note:
- Not for Siemens/Unify OpenStage 5, 15(G), and 20 as these devices do not have a headset jack.
- Not compatible with Aastra/Mitel models with RJ9 connector (4-pin).


4. Setup Instructions
Follow these steps to set up your Callez C500QRJ45 headset:
- Connect the Headset to the QD Cable: Align the Quick Disconnect (QD) plug from the headset with the QD socket on the RJ45 cable and push them firmly together until they click into place.
- Identify the RJ45 Headset Port on Your Phone: Locate the dedicated RJ45-8P4C headset port on your landline phone. This port is typically labeled with a headset icon.
- Plug into the Phone: Insert the RJ45 plug of the QD cable into the headset port on your landline phone. Ensure it is securely seated.
- Using the RJ45 to RJ9 Adapter (If Applicable): If your phone has an RJ9-4P4C headset jack and the adapter was included, first plug the RJ45 end of the QD cable into the RJ45 port on the adapter. Then, plug the RJ9 end of the adapter into your phone's RJ9 headset jack.
- Adjust the Headset: Place the headset on your head. Adjust the headband for a comfortable fit. Position the microphone boom approximately 1 inch (2.5 cm) from your mouth.



Setup Video Guide:
5. Operating Features
The Callez C500QRJ45 headset is designed for ease of use with several integrated controls.
Headset Adjustments:
- Adjustable Headband: Slide the headband to fit various head sizes for optimal comfort.
- 330° Rotatable Microphone Boom: The microphone boom can be rotated 330 degrees, allowing the headset to be worn on either the left or right ear.
- Flexible Microphone: The microphone boom is flexible, enabling precise positioning for clear voice pickup.
- Soft Ear Cushion: The soft leatherette ear cushion provides comfort for extended wearing periods.

Inline Controls:
The QD cable features an inline control unit for managing calls.
- Microphone Mute Switch: Slide the switch to 'ON' to activate the microphone or 'OFF' to mute it.
- Volume Control Wheel: Roll the wheel up or down to adjust the listening volume.
- Shirt Clip: Use the integrated shirt clip to secure the cable and prevent tangling.

Quick Disconnect (QD) Feature:
The Quick Disconnect feature allows you to detach the headset from the phone without interrupting the call, providing mobility away from your desk.
- To disconnect, simply pull apart the two halves of the QD connector.
- To reconnect, align and push the two halves together until they click.
6. Maintenance
Proper care ensures the longevity and performance of your headset:
- Cleaning: Use a soft, dry cloth to clean the headset and cables. Do not use liquid cleaners or solvents.
- Storage: Store the headset in a clean, dry place away from extreme temperatures and direct sunlight.
- Cable Care: Avoid sharp bends or excessive pulling on the cables to prevent damage.
- Ear Cushions: Replace ear cushions if they become worn or damaged to maintain hygiene and comfort.
7. Troubleshooting
If you encounter issues with your headset, refer to the following common problems and solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| No sound from headset |
|
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| Microphone not working |
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| Poor audio quality / Static |
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| Headset does not fit comfortably | Headband not adjusted. | Adjust the headband to fit your head size. |
8. Specifications
| Feature | Detail |
|---|---|
| Brand | Callez |
| Model Number | C500QRJ45 |
| Connectivity Technology | Wired |
| Headphone Jack | RJ45-8P4C JACK |
| Ear Placement | On Ear |
| Form Factor | On Ear |
| Microphone | Noise Cancelling, Flexible Boom, 330° Rotatable |
| Controls | Inline Volume Control, Microphone Mute Switch |
| Additional Features | Adjustable Headband, Quick Disconnect (QD) Cable, Lightweight |
| Material | Polyurethane (PU) ear cushions |
| Item Weight | 6.94 Ounces |
| Color | Black |
9. Warranty & Support
Warranty Information:
Callez offers a 45-day money-back guarantee and a 2-year worry-free warranty for this product. This warranty covers manufacturing defects and ensures product reliability.
Customer Support:
For any questions, compatibility inquiries, troubleshooting assistance, or warranty claims, please contact Callez customer support via email at sales@callez.net. Please provide your model number (C500QRJ45) and a detailed description of your issue for prompt assistance.