When you want to connect a 330 dollar thing to a 5000 dollar router, a consumer oriented forum like this is not the best place to get an answer. Better ask Cisco, especially since your question is rather vague.
Then you can explain to them what you're looking for, because I'm rather sure it isn't a "fiber".
i am looking a Single Mode Fiber which compatible with Cisco router 4431, can i choose this https://www.cisco.com/c/en/us/products/collateral/interfaces-modules/transceiver-modules/datasheet-c78-733586.html please help, urgent!
Link fixed by moderator.