4×6″ Wall-Mount Postcard and Photo Frame. Designed in SketchUp, this thin-bezel frame supports both portrait and landscape orientations using a simple mounting bracket. The model includes three parts: the frame, a backing piece with a mount, and a wall-mount bracket. The postcard shown measures 100×150 mm, which isn’t standard; 4×6″ is the more common size for both photos and postcards.