HI! I'm new so I hope this works. The little plastic balls with the bell inside (you didn't mention they are like MESH plastic) so they can be carried around the house (SO FUNNY to look at)! I have been buying them for about 40 years, and we call them "Bicky Balls". So far Sammy & Spooner have been here 3 months and none have been stepped on yet, so there are around 20 on the floor about now!! I keep buying them....can't imagine being without them!!! Love, Jean & Bruce