SIHOO Doro C300 Pro Ergonomic Office Chair User Manual

1. Introduction

Thank you for purchasing the SIHOO Doro C300 Pro Ergonomic Office Chair. This manual provides essential information for the safe assembly, operation, and maintenance of your new chair. Please read these instructions carefully before use and retain them for future reference.

Image 1: SIHOO Doro C300 Pro Ergonomic Office Chair in gray.

2. Safety Information

• Ensure all parts are present and undamaged before assembly. Do not use if any parts are missing or faulty.
• Assemble the chair on a soft, flat surface to prevent damage.
• Do not stand on the chair.
• Do not use the chair as a step stool.
• Keep children away from moving parts during adjustment.
• Maximum weight capacity: 135 kg. Do not exceed this limit.
• Regularly check all bolts and screws to ensure they are tight.

3. Package Contents

The SIHOO Doro C300 Pro chair package includes the following items:

• Chair components (backrest, seat, armrests, headrest, gas lift, base, wheels)
• Assembly tools
• Japanese instruction manual (for reference, English instructions provided here)
• Spare parts
• White gloves (for assembly)

4. Assembly Instructions

Follow these steps to assemble your SIHOO Doro C300 Pro chair. It is recommended to have two people for assembly due to the weight of some components.

1. Unpack all components and lay them out on a soft, clean surface.
2. Attach the wheels to the chair base by pushing them firmly into the holes until they click into place.
3. Insert the gas lift into the center hole of the chair base.
4. Attach the mechanism to the underside of the seat cushion using the provided screws. Ensure the front of the mechanism faces the front of the seat.
5. Carefully place the assembled seat onto the gas lift.
6. Attach the backrest to the seat mechanism using the designated screws.
7. Install the armrests to the sides of the seat, securing them with screws.
8. Attach the headrest to the top of the backrest.
9. Once assembled, test all adjustments to ensure proper function.

5. Operating Instructions (Adjustments)

The SIHOO Doro C300 Pro offers multiple adjustment features for personalized comfort:

5.1. Headrest Adjustment

Image 2: Illustration of headrest adjustment mechanism.

The 3D mechanical headrest can be adjusted in multiple directions:

• Height Adjustment: Move the headrest up or down by 4.5 cm.
• Depth Adjustment: Move the headrest forward or backward by 6.5 cm.
• Angle Adjustment: Tilt the headrest up to 20 degrees to support your neck and head effectively.

5.2. Backrest Reclining Function

Image 3: Visual representation of reclining angles (105°, 120°, 135°).

The chair features a smart gravity mechanism that automatically adjusts the reclining resistance based on your body weight. The backrest can be locked in three positions:

• Upright: 105° for focused work.
• Relaxed: 120° for a slight recline.
• Deep Recline: 135° for resting or taking a break.

5.3. Automatic Adaptive Lumbar Support

Image 4: Detail of the automatic adaptive lumbar support.

The Doro C300 Pro is equipped with a domino automatic adaptive lumbar support system. This system automatically adjusts to the curve of your spine when you sit, providing continuous support and reducing fatigue during long periods of sitting. It features a soft mesh and high-rebound support material that slides up to 2.5 cm to conform to your back.

5.4. 6D Linked Armrests

Image 5: Diagrams illustrating the six directions of armrest adjustment.

The ergonomic 6D linked armrests offer extensive adjustability:

• Height: Adjust up or down by 6.8 cm.
• Front/Back: Move forward or backward by 4.8 cm.
• Left/Right: Swivel left or right by 70°.
• In/Out: Adjust inward or outward by 8 cm.
• Upward Angle: Tilt upward by 35°.
• Linked Movement: The armrests move in conjunction with the backrest when reclining, providing continuous support for your arms and shoulders.

5.5. Backrest Height Adjustment

Image 6: Diagram showing the 4-stage backrest height adjustment.

The backrest can be adjusted in 4 stages, allowing for a 6 cm height range. To adjust, lift the backrest to the desired position. To reset, lift it to the highest point, and it will automatically return to the lowest position.

5.6. One-Hand Control Mechanism

Image 7: Illustrations of the one-hand lever for height, seat depth, and recline adjustment.

The chair features a convenient one-hand lever for intuitive control of key adjustments:

• Height Adjustment: Pull the lever up to adjust the chair height (adjustment range 10.7 cm). Release to lock.
• Seat Depth Adjustment: Rotate the lever forward to adjust the seat depth (adjustment range 2.5 cm). Release to lock. This waterfall-shaped seat cushion precisely distributes pressure on the thighs and hips.
• Reclining Angle Adjustment: Rotate the lever backward to adjust the reclining angle (105°-120°-135°). Release to lock.

6. Maintenance

• Cleaning: Wipe the chair with a soft, damp cloth. Avoid harsh chemicals or abrasive cleaners.
• Mesh Care: The Cloud high-elastic mesh is breathable and durable. For deeper cleaning, gently wipe with a mild soap solution and rinse with a damp cloth. Allow to air dry completely.
• Inspection: Periodically check all screws and bolts for tightness. Re-tighten if necessary.
• Moving: When moving the chair, lift it rather than dragging it to prevent damage to the wheels and floor.

7. Troubleshooting

• Chair does not adjust height: Ensure the gas lift lever is fully engaged or disengaged as required. Check if the gas lift is properly inserted into the base and seat mechanism.
• Chair wobbles: Check all assembly screws and bolts, especially those connecting the base, mechanism, and seat. Tighten any loose connections.
• Reclining function is stiff or not locking: Verify that the one-hand control lever for recline is functioning correctly. Ensure no obstructions are preventing the mechanism from moving freely.
• Squeaking noises: Apply a small amount of silicone lubricant to moving parts or joints if persistent squeaking occurs. Avoid oil-based lubricants on plastic components.
• Wheels not rolling smoothly: Check for debris (hair, dust) caught in the wheels. Clean them thoroughly.

8. Specifications

9. Warranty and Support

The SIHOO Doro C300 Pro office chair comes with a 3-year quality warranty from the date of purchase. This warranty covers manufacturing defects and material flaws under normal use.

If you encounter any issues, defects, or have questions regarding your product, please do not hesitate to contact our customer support team. We are committed to ensuring your long-term satisfaction with your SIHOO product.

For support, please refer to the contact information provided with your purchase documentation or visit the official SIHOO website.