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The Agilent 1250-1477 is a general-purpose grade, type-N male to BNC male adapter with impedance 50 ohms. Connector Type: Type-N female, BNC male Grade: General Purpose Frequency Range: dc - 4 GHz Return Loss: 32 dB to 1.3 GHz Overall Length: 40.38 mm (1.59 in) Diameter: 17.52 mm (0.69 in)