Vacuum thermoforming is when heated plastic sheeting is placed over a male mold. Air between the mold and the plastic sheet is vacuumed out pulling the sheet very tightly to the mold walls. These products tend to have sharp details, molded textures and undercuts. The products produced are usually shallow and can be made from heavy or thin gauge plastics. The thicker the plastic sheet is the harder it is to form super tight or sharp corners. Vacuum forming is a favored method used when creating transparent products. This type of molding is considered low level technology and can even be done using a household vacuum. This molding technique is a cost effective method and is often used in place of more expensive sheet metal and fiberglass products. After the forms are created they will need further processing. Excess sheet material must be cut away and any holes needed for riveting will be punched.