These are wooden beads meant for making biting or chewing toys for pet birds. These wooden beads are cut from bird-safe tree branches, and well sun-dried to prevent any mold growth. The beads have 5mm holes drilled for stringing purposes. There are two sizes (1/2 and 1 inch). Length is about 1 inch for both sizes.
Typically the biting or chewing toys are combined with different types of wooden or other natural materials, such as different types of woods, leaves, grasses, loofah, barks, papers etc. However. you may also use these beads on stand-alone without stringing them with other materials.
Note: It is very important to keep them very dry. Barks are great to bite on, however ensure they are dry. Otherwise, you may remove the barks as well before giving them to birds.