The AS-907 crosswhistle is the starter model of Altus made of'new silver'. New silver is very hard and can withstand a blow that will reduce the damage to the flute. The Altus crossflute has a very open and clear sound with a perfect intonation. Altus is not satisfied with just any whistle, they always strive to be the best in the price range. You can also tell when you play the flute. You can tell the difference between an ordinary student flute and an Altus student whistle.