Bearing: maximum 20kg (including drawer dead weight) vertical and lateral with perfect stability hydraulic damping structure to realize the self-closing function brought by the soft and silent overall self-closing structure of drawer closing, avoiding accidental pulling out of the guide rail with self-cleaning function, without additional maintenance work, solid and elastic guide rail to ensure the most perfect guidance of steel column: the control force with accurate operation performance puts the drawer on the slide rail and pushes it in place, the plug-in installation can be completed. The rotating pawl wheel can realize continuous height adjustment. The partial pull-out and full pull-out slide rails can be flexibly interchanged without changing the cabinet body, height and drawer panel size.