Boxiecat Air is flushable, but Boxiecat clay litter should not be flushed down toilets.
More about Boxiecat clay litter:
Due to the fact that clumping litter expands upon contact with liquids, they should never be flushed down toilets or poured into drains. Flushing clay litter may cause plumbing issues.
In addition, most cities advice against flushing any type of cat litter for sanitary and water quality reasons regardless of a litter brand being marketed as "flushable."
Boxiecat recommends scooping litter into a baggie, tying it closed, then disposing of used litter in a trash receptacle. Boxiecat Scoop & Tie Litter Bags make a convenient option that is also eco-friendly as they contain an additive to make plastic break down faster than it normally would.