Is important to know several key points or we can help to choose the right module:

1. The intended speed (e.g. 1Gbps, 10Gbps, 100Gbps, etc.)
2. The wavelength (e.g. 850nm, 1310nm, 1550nm, etc.)
3. The type of media (e.g. Copper, Single Mode Fiber - SMF, Multi-Mode Fiber - MMF)
4. The distance (e.g. 550m - SR, 10km - LR4, 40km - ER4, 80km - ZR4, etc.)
5. The connector type (e.g. LC, SC or ST)
6. If support Monitoring (e.g. Digital Diagnose Monitoring - DDM, Digital Optical Monitoring -DOM)
7. Special features:
 a. Common Public Radio Interface (CPRI)
 b. Bidirectional (Bidi)
 c. Tunable
 d. Double Density (DD)
 e. Forward Error Correction (FEC)
 f. Right to Use (RTU)
 g. CWDM
 h. DWDM