Office Chair Seat Bottom

The bottom of a standard office chair seat is typically composed of three main parts: chair legs, casters, and a gas lift rod. Some chairs are also equipped with a base plate. Common styles include five-star base, bow base, fixed wooden base, and swivel base. The following provides an introduction from two aspects: components and common styles.

Components

• Chair Legs: As the core component supporting the entire structure, chair legs come in a variety of materials, each with distinct functions. Metal chair legs (such as steel or aluminum alloy) offer strong load-bearing capacity and high durability, with surfaces often treated with polishing, baking paint, or electroplating for rust prevention and aesthetic appeal. Nylon chair legs are lightweight and quiet, suitable for scenarios sensitive to movement noise. Solid wood chair legs are commonly used in high-end models, enhancing texture through natural grain patterns. Structurally, chair legs often feature a five-star design (five-claw structure), which enhances stability through radial distribution and prevents tipping risks.
• Casters: Installed at the ends of chair legs, casters directly affect the mobility experience. Standard casters are suitable for hard floors (such as tiles or concrete), while PU casters use soft materials for quiet movement and protection against scratches on wooden floors. All casters support 360° rotation, ensuring flexible movement of the chair in all directions.
• Gas Lift Rod (Height Adjustment Rod): Located at the center of the chair legs, connecting the base plate to the seat, it is the core component for adjusting seat height and rotation. It contains high-pressure gas inside, with height adjustment controlled by pressing a handle. Some high-end models also integrate rotation functions to meet users' dynamic adjustment needs for sitting posture.
• Base Plate: Although not directly exposed on the bottom appearance, the base plate plays a crucial functional role. It connects the gas lift rod to the seat, controlling the recline angle, locking functions, etc. Some base plates also integrate explosion-proof devices to enhance safety during use.

Common Styles

• Five-Star Base: Primarily made of metal or nylon, featuring a five-claw design paired with universal wheels, it offers strong load-bearing capacity and flexible movement. Commonly found in ergonomic chairs and gaming chairs, it is suitable for scenarios requiring frequent sitting posture adjustments.
• Bow Base: The metal frame is bent into a bow shape, directly resting on the floor without wheels. It is structurally stable, simple, and durable, often used in conference chairs and staff chairs, suitable for fixed-position use.
• Fixed Wooden Base: Made of solid wood with diverse shapes (such as round or square), it lacks mobility but offers excellent stability. Commonly found in vintage or high-end office chairs, it emphasizes decorative appeal and a sense of solidity.
• Swivel Base: Paired with height adjustment functions, it connects the seat to the support frame at the bottom and supports 360-degree rotation. Commonly found in executive chairs and adjustable office chairs, it meets multi-directional interaction needs.