The invention relates to an apparatus for delivering mechanical energy to an expanse of skin, said apparatus comprising: a skin-contactable element having a skin-contactable surface comprising a first and second sub-surface, wherein said skin-contactable element comprises an agent selected from the group consisting of a benefit agent, an apparatus-enhancing agent, and combinations thereof； a motor； and a transfer member for transferring mechanical energy from said motor to said skin-contactable element in order to provide periodic motion to said skin-contactable surface； wherein said periodic motion comprises a first periodic motion of said first sub-surface and a second periodic motion of said second subsurface such that said second subsurface moves in a disjoint relationship with respect to said first sub-surface.
