30 in. x 80 in. Primed 2-Panel Square Hollow Core Composite Interior Door Slab with BoreDiscover sophistication and effortless grace with the Masonite Smooth 2 Panel Square Hollow Core Primed Composite Interior Door Slab with Bore. The standard setter for all composite wood doors, expert craftsmanship yields a sturdier door that resists warping, shrinking, and cracking better than solid wood doors. Choose from a range of designs, including coordinating bi fold and factory prehung single or double prehung units. The classic panel design