Car stereo head units come in all shapes and sizes, which can make it tricky to figure out how to upgrade. The only official aftermarket head unit standard is known as “single-DIN,” which specifies a height of about 2 inches and a width of about 7 inches.
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Most cars had either a single or double DIN radio, with "double" meaning twice as much as a single DIN. But there are thousands of vehicles with head units that fall into a strange in-between category. These head units are usually referred to as 1.5 DIN or Din-and-a-half.
“1.5 DIN” or “Din-and-a-half” refers to head units that sit somewhere between single and double DIN units. Simply put, they are half the height of double DIN units—or half the height of single DIN again.
While dozens of automakers have used the single and double DIN form factors, 1.5 DIN is much less common. It is most often found in GM vehicles, including Chevy, Cadillac, and GMC cars and trucks.
