Runescapers Here

[ToshX]

When you go from a member to a free user, your items are deemed "member objects".

But they don't disappear unless you drop them and don't pick them up or something. These "member objects", however, cannot be used, traded, or sold(unless it is an equipment that is already equipped, in which case it would have its stats decreased to 0). They turn back into their old items when you go back into a member world.