The ones with an arm under the mattress work fine
We have used the ones with the arms that go under the mattress. The wood rail actually gives it more support as the mattress "gives" enough so they can be placed inside up against the frame. Don't need the ones that go all the way under the bed with an anchor system ( usually a disc that goes flat against the mattress side. The wood rail keeps it in place and secure. Folds up and gets stored when not in use. Used for years with my grands, but they are bigger now so permanently stored under the bed in my bricks and sticks guest room. Used for the drop down bed (princess bed) and for bunk beds.
Good luck.
__________________
|