These compatible modules can always save my budget. At first, we've worried about the compatibility because of the failure we once had with our previous suppliers. I found FS modules with high compliment. There are many positive comments about their transceivers. I tried because they've promised me a good after sale service. When I received these transceivers, the delicate package really impressed me a lot. Then I put it on my Cisco switch, it can completely compatible with my switch, just like they've promised me, every transceiver will be tested on original switch before delivery. FS really is our trustworthy partner.