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CSS MECHANISMS

Differences between CSS 2, CSS 3 and CSS 4

Erhun Technical Content TeamJuly 15, 2026

SHORT ANSWER

CSS 2 provides the core function and a short-trim option; CSS 3 adds standard, stop/stepped and eco variants; CSS 4 uses a reduced-screw structure with round plastic or zamak surface options. CSS 4 ABS differs through single-screw assembly and an ABS structure suitable for knock-down shipment.

Shared operating principle

The CSS family changes standard seating into deep seating and creates a single-bed function in a three-seat sofa.

Fixed or removable back-cushion selection should be verified through sample assembly using the actual foam and upholstery tolerances.

Selection by variant

Choose the relevant CSS 3 variant when stop/stepped movement or an eco body is required. For CSS 4, decide between short or standard trim and plastic, zamak or ABS surfaces according to the furniture design.

Before serial production, check screw count, assembly order, left-right orientation and upholstery contact points against the technical drawing.

Let's choose the right mechanism for your product.

Share your model drawing, dimensions and target function, and our technical team will suggest a suitable product.