Features：
1. Elder arm, life like texture, realistic blood vessels
2. Accurate anatomical structure, include cephalic vein, basilic vein, median cubital vein, median antebrachial vein, etc.
3. Venipuncture
① Intravenous injection, infusion, blood collection, blood transfusion etc.
② Realistic feedback, blood backflow
4. Skin and vessel are replaceable