I took a pea out of a pea whistle,the pea was solid plastic,kinda' like from a soft air gun type BB,I had to tweak the metal a bit,but I bent it back in shape,& without the pea it didn't strike a note,I even tried bending the metal in various way's to get some tunes out of it,but no go,I placed the pea back in & closed it,It worked again!It was a $3.50 whistle from Sports Chalet,the brand is Champion,I still have it,though it's not a user,for myself! I have No affiliation with the above named store!