Features：
1. Lifelike child leg, accurate anatomical structure
2. Bone marrow puncture
① Clear body features: patella, tibia and tibial tuberosity
② Realistic feedback, bone marrow outflow
③ Replaceable skin and bone
3. Femoral venous puncture;
① Touchable femoral pulse;
② Correct puncture with a sense of empty and has blood back flow
③ Replaceable Injection pad