1.Signal transmission smooth,one year guarantee. 2.Free shipping charge for exchange goods. 3. Low cost because of manufacture Name: 1550nm Erbium-Doped Fiber AmplifierDescription:Mode No: HKTGFD-001Specifications:World famous PUMP laser, low distortion, wide frequency band, high optical output power Import high quality EDF, high energy conversion efficiency. Humanized display of using time, ...