Refrigerant Weight Scale
WARNING: This page is about a different car, the 2008 Infiniti EX35. However, it is still accessible from the selected car via links, so may be relevant.
Verify that no refrigerant other than HFC-134a (R-134a) and specified lubricants have been used with the scale. The hose fitting must be 1/2"-16 ACME if the scale controls refrigerant flow electronically.
Courtesy of NISSAN MOTOR CO., U.S.A.