All pet reptiles need supplementary calcium to balance their diet. For lizards and snakes, this can be easily done with gutloading and calcium powder, but for aquatic turtles, this gets tricky because most turtles can only eat in water, and calcium powder gets washed off by water.
The Zoo Med Turtle Bone is a floating block of calcium that aquatic turtles and tortoises can gnaw on as needed to fulfill their dietary calcium requirement. As a bonus, the Turtle Bone’s rough surface helps keep turtle and tortoise beaks trimmed and in good condition.