Functions: 1. Made of high quality plastic, solid, durable and wear-resistant.2. Its height is adjustable and is suitable for exercises with high bar, middle bar and lower bar.3. Perfect billiard impact trainer for beginners or professional players.4. Suitable for nine balls, black eight, snooker etc. 5. Detachable design, lightweight and easy to carry and store.Specifications:Material: plasticColor: blackFront support size: approx. 62*53mm/2.44*2.09inchHole diameter: approx. 20mm/0.79inchRear triangle support length: approx. 70 mm/2.76 inches. Weight: approx. 25gPacking list:1 * Billiard Stroke Exerciser