tubing sealers , whether hand held or desk mounted , heat seal liquid filled plastic tubing on command to develop sealed liquid filled easily separable segments serially attached to one another . the sealer generates a source of rf energy to heat seal the plastic tubing on placement of the tubing between a fixed jaw and a tubing compressing moveable ground jaw . the moveable ground jaw serves as a heat sink to dissipate heat and prevents a heat buildup during rapid repetitive operation of the sealer . the configuration of the moveable ground jaw coming in contact with the tubing primarily , but in combination with the degree of compression of the tubing and the rf power applied , controls both the integrity of the seal and the ease with which the sealed segments of tubing can be separated from one another .