The blt-1.25 is a standard large triangle at 1.25 mm thickness. The black material comes from a related molecular family to our best-selling brown series, but with some wonderful tonal differences. Most players tell us it "cuts through the mix" better than the brownies, so it's ideal in ensemble lead playing -- as long as a banjo isn't within 1000 yards. Play it against everything you can get your hands on. NOTE: These are also REALLY GOOD on mandolin!