Reading the codeD180 means a D section belt with a 180 inch inside length (4572mm). Metric sizes may show the inside length (Li) or the datum length (Ld), which on D section is 75mm longer, so check which your belt uses.
Which brand?Every belt here fits the same D section pulleys. Choose Optibelt for the longest life on hard-working or continuous drives, or a value brand for occasional-use machinery.
Is it really D section?A D section belt is 32mm wide and 19mm deep. Belts this size are often banded on heavy drives, and American 8V belts are narrower, at 25mm, so measure carefully.