Vascular BV 520 will detect the blood flow with average velocity and detect the blood stream status of arterial/venous by 8.0MHz. It also detect blood speed during recovery and blood flow of peripheral vessel. It can detect the peak and average blood speed. The working temperature may occur with 10 40?. The display screen has LED with 20bit. It has doppler frequency with 100 to 7000Hz. The product run input voltage with DC 9V 1000mA. The product's Battery has 7.4V/900mAh and rechargeable Lithium. This product delect the pulse rate and show PR simultaneously, phlebostenosis, vein occlusions and subsection systolic pressure of toes and fingers. It can be utilized to listen the temporo mandibular joints , assist doctor to check the conditions of the joints and predict the result of treatment.