Classic Office Chair Installation

The installation steps for a classic office chair are as follows:

Step 1: Install the Chair Wheels
Insert each chair wheel into the assembly holes of the five-star base one by one, ensuring that each wheel is fully embedded and rotates smoothly. If there is a slight deviation between the chair wheel and the base hole, adjust the angle slightly and reinsert it, avoiding forced pressing that could damage the components.

Step 2: Install the Gas Lift
Align the thicker end of the gas lift with the center hole of the five-star base, place it vertically, and press gently until it is fully embedded. The gas lift is the core component for the chair's height adjustment function. Ensure it is perpendicular to the base during installation to avoid tilting, which could cause stuttering or air leakage during subsequent use.

Step 3: Secure the Base Plate to the Seat Cushion
Place the base plate on the bottom of the seat cushion, paying attention to the orientation of the base plate (usually marked or with grooves corresponding to the seat cushion structure). Align it with the four screw holes, then use a screwdriver to screw each screw in 3-4 turns before tightening them one by one. This step requires ensuring that the screws are tightened evenly to avoid gaps between the base plate and the seat cushion, which could affect stability.

Step 4: Connect the Seat Cushion to the Gas Lift
Align the assembled seat cushion with the top of the gas lift and insert it vertically until the base plate hole fully covers the gas lift. Keep the seat cushion level during insertion to avoid wear at the connection between the gas lift and the base plate due to angular deviation.

Step 5: Install the Backrest
Align the bottom sides of the backrest with the armrest installation positions on both sides of the seat cushion. First, secure the bottom of the backrest with screws from the bottom of the armrest brackets, then align the back of the backrest with the installation holes on the seat cushion brackets and use two wrenches to lock the screws in place. This step requires ensuring that the backrest is perpendicular to the seat cushion to avoid tilting that could affect sitting comfort.

Step 6: Install the Armrests
Press the button below the armrest surface and insert the left and right armrests into the holes of the armrest brackets respectively. A 'click' sound indicates that they are properly installed. After installing the armrests, test their adjustment functions (such as height and angle adjustment) to ensure smooth movement without jamming.

Step 7: Secure the Headrest
Place the headrest in the middle position at the top of the backrest, press the headrest installation area to make it fit more closely with the backrest, then insert a screw through the headrest fixing clip and tighten it. The height of the headrest should be adjusted according to the user's height, and its stability should be checked after installation to avoid wobbling.

Precautions:

1. Before installation, check that all components are complete to avoid discovering missing parts midway and having to disassemble repeatedly.
2. When tightening screws, do it in stages to avoid over-tightening a single screw, which could prevent other screws from aligning properly.
3. After installation, test all functions (such as height adjustment, rotation, and backrest adjustment) to ensure there are no abnormalities before use.