SQS350H is equipped with a classic hexagonal boom section with a simple structure, good centering and strong cross-section bending resistance; The single-cylinder with cable synchronous telescopic technology enhances boom telescopic efficiency. The automatic hook retracting device maximizes preparation time before and after operation, prevents the hook from swinging during driving, and improves driving safety. The anti-overwinding protection device prevents the hook from overwinding due to user negligence or unskilled operation., and effectively reminds the operator to stop retracting the hook to prevent personal and property safety caused by wire rope breakage; vertical square box legs improve the vertical cylinder force and avoid cylinder damage caused by unequal working sites; the double pump confluence system makes the hook lifting speed faster.