supposedly spin , but you have to use both hand and force it . so far , be work fine for lot of bottle \/ little part as well as my pump part that need wash . we be currently use 4 oz . glass bottle -lrb- and it be fine -rrb- , but I bet it will be too flimsy to handle 8 oz . glass bottle -- which I will be switch to in the next few month . if that be the case , my rating will need to be downgrade to 1 star .