How to Assemble an Office Chair

The assembly steps for an office chair are as follows:

1. Install the casters and chair base
   Insert each caster into the mounting holes of the five-pronged chair base one by one, ensuring that each caster is fully engaged and not loose. After installation, place the gas lift vertically into the center hole of the chair base, and confirm that the bottom of the gas lift is flush with the contact surface of the chair base to avoid instability during subsequent use due to tilting.

2. Install the seat plate and seat
   Place the seat plate on the bottom of the seat, paying attention to the orientation of the seat plate (usually there are clear markings or grooves corresponding to the seat structure). After aligning the four screw holes of the seat plate with those of the seat, use a screwdriver to screw in the four screws one by one for 3-4 turns to ensure that the seat plate is initially fixed, and then tighten all the screws in sequence. Key point: Avoid tightening a single screw all at once; tighten them alternately to prevent the seat plate from shifting.

3. Connect the backrest and seat
   Align the gas lift connector at the bottom of the seat with the center hole of the seat plate and insert it to ensure that the gas lift fits perfectly with the seat plate. Align the two sides at the bottom of the backrest with the armrest mounting positions on both sides of the seat, first insert the bottom of the backrest and use two screws to initially fix it from the bottom of the armrest bracket, then align the mounting holes at the back of the backrest with those of the seat bracket, and use two wrenches to tighten the screws (one end fixes the screw, and the other end rotates the nut) to complete the firm connection between the backrest and the seat.

4. Install the armrests
   Press the elastic button below the armrest surface (some models have a snap-fit design), and align the left and right armrests with the holes of the armrest brackets respectively and insert them. A "click" sound or the disappearance of resistance indicates that they are properly installed. Note: The armrests should be level with the seat to avoid unevenness affecting comfort during use.

5. Install the headrest
   Place the headrest vertically in the middle position at the top of the backrest and press the mounting part of the headrest to make it fit snugly against the backrest. Insert two screws through the holes of the headrest fixing clips, first screw them in for 3-4 turns one by one for initial fixation, and then tighten them alternately. Tip: If the headrest is height-adjustable, test the sliding or rotating function after installation to ensure it works properly.

Precautions:

• Before assembly, check that all components are complete to avoid interruption of the process due to missing parts.
• When tightening screws, use tools of the corresponding specifications (such as a cross-head screwdriver or wrench) to avoid slipping.
• After installing the gas lift, test the lifting function to ensure there is no jamming or air leakage.
• After completing the assembly, it is recommended to shake the chair to test its overall stability, focusing on checking the connections of the casters, gas lift, and backrest.