This sight glass is suitable for different types of refrigerant,Like R12, R22, R134a, R404a, R401A,R407 R502.

Sizes:

           TYPE        CONNECTION           LENGTH

          FL-1/4        1/4 × 1/4                    67MM

          FL-3/8        3/8 × 3/8                   77.5MM

          FL-1/2        1/2×1/2                    77.5MM

          FL-5/8        5/8 × 5/8                    82MM

          FL-3/4        3/4 x 3/4                    82MM

          FL-7/8        7/8 × 7/8                    82MM