Bushman was never satisfied with the life expectancy or responsiveness of the brass reeds used in other harmonicas. When metal experts told them that phosphor bronze offered greater hardness, tensile strength, elasticity, and toughness than brass, they ordered some and began cutting it into reeds for the Delta Frost. They knew they would be gaining durability with the phosphor bronze, but they had not counted on the wonderful, unique, gritty, fat tone that it produces. With its whiskey smooth, stainless steel cover plates, and its plastic comb that's been milled and rounded for comfort, this instrument is up to the task of helping to keep the memory of Frank Frost alive. Most harmonicas have brass reeds, but the Delta Frost has longer-lasting, copper-colored, phosphor bronze reeds that not only provide hours of dependable play, but they produce a dirty, bluesy tone.