Glass door inserts are manufactured only for fiberglass exterior doors. Plastpro brand fiberglass doors are a quality rot proof door slab for prehung doors and therefore a good choice for cost effective home improvements. Interior doors are manufactured differently and the glass is built into the door at the time of manufacture. The exterior doors are injection filled with polyurethane and are solid not hollow and have different decorative profiles. These profiles give the door 2-8 recessed panels for customers that would prefer a solid choice.Exterior chinese infusion mat suppliers doors can be manufactured to receive removable glass inserts or to have non removable flush glazed glass panels. The difference is that the flush glazed glass panels are made as a glass unit then sealed into the door during manufacture and are not removable, which is not a good feature in our opinion.The removable option is recommended for many reasons:1. Selection. Wide range of choices. You can order clear or textures, Decorative or plain! The flush glazed typically only comes clear and plain.2. Hurricane Impact choices. The flush glazed fiberglass doors with glass are not impact resistant. The removable inserts are standard tempered or hurricane impact. Therefore, to be prepared for a storm, the glass etching is recommended on the removable inserts that are available in hurricane impact choices.3. Cost effective. In the event of breakage of the glass, it can be replaced without the need to replace the doors. Decorative removable glass door inserts are 1\u2033 thick and provide better insulation with the increased airspace. The flush glazed doors are offered at 1\/2\u2033 only.