Method of thermoforming a thermoformable polymeric sheet material over an insert

A method of thermoforming a thermoformable polymeric sheet material over an insert comprising:

• (a) supplying an insert having at least two vertically disposed walls and at least two horizontally disposed walls extending from an upper portion of each of said vertically disposed walls, and a horizontal connecting wall extending between a lower portion of said vertically disposed walls, wherein the horizontally disposed walls extending from said upper portion of said vertically disposed walls intersect with each of said vertically disposed walls at an angle of 60° to 120°, thereby providing two undercut locations, wherein said insert includes one or a plurality of vertical ports extending through the horizontal connecting wall and one or a plurality of horizontal ports extending through the vertically disposed walls, said vertical and horizontal ports being configured to assist in vacuum drawing of the thermoformable polymeric resin sheet material;
• (b) positioning said insert into a vacuum forming mold and supplying a thermoformable polymeric resin sheet material that is positioned over said insert and heating said thermoformable polymeric resin material along with the application of vacuum wherein said thermoformable polymeric resin engages with said insert and substantially conforms to the two undercut locations thereby locking said insert into said thermoformable polymer resin.