Materials which can be used with the heat sealers include foil, poly coated Kraft paper, and other plastic materials. There are various sizes and designs the sealers are available in. if you want to ensure stronger and thicker seal, you can consider using sealers with flat sealing wires. If the film you are using is not thicker and you want to make a seal that is less visible, you can use a sealer with round wire.

The sealing bar is made of a heat resistant material which may be the silicon. The main purpose of having a heat resistant material in the bar is that it has to come really close to the heated wire. The film is placed over the wire and then the bar is pressed upon it. As soon as the pressing bar comes close the wire, it gets heated and melts the film to make the seal. Sealing bar has springs that allow the user to apply adequate amount of pressure.

When the pressing bar is closed and you apply pressure on it, a micros-witch turns on to let the electric current to run between the connector posts. This conduction of current heats the wire. When the micro-switch is on, it also turns on the sealing light which indicates that sealing has begun.

When the micro-switch is turned on, the sealing wire gets heated. This heat from the wire melts the film. The pressure of the upper bar presses the upper part of the film into the lower part. Both films mend to make the seal.