Littlel bubble and vacuum are most important technique used on face cleaning machine. Vacuum could slightly lift skin keep the pores open. Liquid flow plus ultrasound makes little bubble promote dirty dissolve on pores can be cleaned out. Vacuum and little bubble all hapen on this head, the plastic head could be replaced. If want it as consumable could buy from us any time, buy in seperatly ok.After face cleaning treatment the skin disturb by machine, after clean dirty out pores need a little monment to get use to it. Clam spray could help for skin calm down and pores refining.