This is an elongated, triangular cut from the bottom of the Sirloin adjacent to the Flank and Round. The Tri-Tip steak is cut crosswise from this section.
This cut is very popular all along the West Coast, centering in Santa Maria, 170 miles north of Los Angeles, but is not well known in most of the country. In New York, Florence Prime Meats has popularized this cut under the name "Newport Steak", named for the triangular logo on a pack of Newport cigarettes.
Supply is limited because there are only two of these per beast. The photo specimen was a Tri-Tip Roast, untrimmed (#185C). Untrimmed means the membrane and fat (on the back side in photo) have not been removed. This one measured 12 inches long, 7 inches wide at the big end and 2 inches thick at the thickest point, and weighing 2 pounds 3 ounces after fat and membrane were removed
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