Office Chair Base Specifications

There is no unified fixed specification for office chair bases. The common types and their characteristics are as follows:

Common Base Types

1. Ordinary Base (Fixed Type)
   It has a flat-plate structure with no adjustment handles and offers limited functionality. The backrest and seat cushion are fixed and non-adjustable, and the chair cannot recline. It is suitable for low-cost scenarios, such as bow chairs, four-legged chairs, or extremely low-priced swivel chairs. Its design is simple, but it has poor comfort and only meets basic sitting posture needs.

2. Single Reclining Base (Ordinary Reclining Base)
   It is equipped with a small wrench or knob on the side, supporting the reclining function. However, the tilt angle is usually limited to 20°-30° and cannot be locked. After releasing the adjustment device, the backrest will automatically spring back to the upright position. It is commonly found in basic employee chairs or home computer chairs and is suitable for short rest scenarios.

3. Single Reclining Base with Lock (Lockable Reclining Base)
   It has a thicker pull rod or hand-operated switch on the side, supporting the locking of the reclining angle (such as a 90° working mode and a 110° slightly reclined mode). Some models can adjust the tightness of the reclining spring to fit users of different weights. It is commonly found in mainstream-priced office chairs and entry-level ergonomic chairs, balancing functionality and cost-effectiveness.

4. Synchronous Reclining Base (Linked Reclining Base)
   It has a sturdy structure with multiple connecting rods. When reclining, the seat cushion and backrest move in tandem (for example, when the backrest reclines by 25°, the front end of the seat cushion rises by 5°), maintaining body balance and reducing lower back pressure. It is commonly found in high-end ergonomic chairs priced at over a thousand yuan and is suitable for users who work for long hours or pursue comfort.

5. Cable-Controlled Base
   All adjustment functions are integrated into a handle, allowing users to operate without bending over, such as adjusting the height and reclining angle, enhancing user convenience. It is commonly found in high-end ergonomic chairs.

6. Gravity-Sensing Base (Self-Adjusting Reclining Base)
   It is equipped with a built-in gravity-sensing device that can automatically adjust the reclining resistance according to the user's weight without manual adjustment. It fits users of different body types and is commonly found in high-end smart office chairs.

Base Bracket Specifications

The base brackets are mostly made of oval steel tubes, with a common specification of 5cm×3cm, balancing strength and lightweight requirements to ensure the stability and durability of the chair. Some high-end models may use thicker steel tubes or special alloy materials to enhance load-bearing capacity.