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Dear Ahmed, we are using fs.com SFP since a long time ago with no problem on 3750G-12S and EHWIC-1GE-SFP-CU on 1941 routers.
In your case, we use the following pair of BiDi SFPs:
https://www.fs.com/keyword/120km&cisco=18508&bidi=18510&searchSubmit=...
