1. A dual-shaft extending structure that makes it easier for passengers in the backseat to see 2. Double-spring design, 3s fast installation 3. One-handed operation, 360° free rotation, and ease of use 4. Wide compatibility; compatible with devices 4.7-13" and headrests 70-158mm 5. Recyclable clamp arm, carbon fiber texture, sand-blasted aluminum main rod, and assurance of safety