NPT SF:2"X4"AOSF 2" x 4" Antique Onyx Travertine Split Face - The natural beauty of travertine makes it ideal for any outdoor space. Whether creating a patio, a walkway, or a pool deck, travertines rich tones and inherent shade variations will add warmth and sophistication to any setting. The natural stone looks help to magnify the elegance of any area.