Erbium doped fibre amplifier (EDFA) is a high performance, small size of the fibre amplifier products. The internal use of a stable semiconductor laser, the high stability of WDM, isolator, and high gain erbium-doped fibre. The product has the advantages of high reliability, high gain and low noise. This is the ideal choice of high power EDFA system, this product uses 5V DC power supply, compact size, easy to integrate in the system to meet the needs of customers.