They do exist. They tend to have tighter link budgets as compared to XFP tunable optics. Don't expect to go as far due to the receiver sensitivity. Jared Mauch > On Jun 6, 2015, at 1:29 PM, Frank Bulk <frnkblk at iname.com> wrote: > > Anyone know if tunable SFPs exist? I've googled around on this, but only > found fixed wave-length SFPs. > > Or of a tunable SFP+ that can operate in SFP port as 1G? > > Frank