Wisepick Air Condition Manifold Gauge Set, R1234Yf R134A Gauge Set, 4 Valve Manifold Gauge Compatible with R1234Yf R134A and R404A Refrigerants. 2 pcs R134A to R1234YF coupler adapters: Brass body, connect with R134A adapters and turn into R1234YF adapter, High adapter for red side, low adapter for blue side.