Yb43x fixed proportional pressure reducing valve has beautiful appearance, reliable quality, accurate proportion and stable operation, reducing both dynamic and static pressure. Yb43x fixed proportional pressure reducing valve uses the pressure difference between the two ends of the piston in the valve body with different cross-sectional areas to change the pressure behind the valve to achieve the purpose of pressure reduction. The pressure reducing ratio of yb43x fixed proportional pressure reducing valve is: 2:1, 3:1, 4:1, 3:2, 5:2, etc. special proportional pressure reducing valve can also be designed according to the requirements of users.