Micro-grooved Sandwich Door Model 3285 Designed to enhance appearances in a variety of applications, this door will augment the look of both homes and businesses alike, The door is distinguished by four evenly spaced micro grooves that run horizontally across each section. This design incorporates the tongue and groove joint between each setion and givess the door an even, symmetrical appearance. Business and homeowners alike will soon take for granted the added durability and insulating value that this double sided steel door offers.