The panels on the Plexidor Pd Door and Pd Wall XL units are manufactured using a solid 3/8 in. sheet of Plexiglass instead of the thermo-pane panel design. This makes the panels virtually indestructible for larger dogs up to 220 lbs. The panels also come equipped with factory installed chew proof aluminum trim around all four edges and on both sides of each panel. This prevents damage to the panels from chewing which sometimes occurs with larger breeds of dogs (e.g. Labradors).