Ballistix Sport LT 8GB Single DDR4 2666 MT/s (PC4-21300) DR x8 DIMM 288-Pin Memory - BLS8G4D26BFSE (Red)
I'm sure you can overclock this, I'd guess it would easily passed the 3000mhz mark and further if you messed with the timings. I have many ddr4 sticks in the low 2000mhz range and all so far have made it past the 3000mhz mark, even my cheapo crucial ddr4 2x 16gb 2133mhz ram is running at 3000mhz.
If you bought a second stick and overclocked the ram past 3000mhz, you would likely see a large bump in gaming performance. I build a 2200g system for a friend recently, I can't remember exactly what ram he had, it was slower ram, but I was able to increase his gaming benchmark results by about 50% by overclocking it. You could run some graphics benchmarks, if you don't have any there are many free ones, overclock the ram and re-benchmark to see the performance increases.