Here is a link to where I buy it.
There is a good description there too.
They are the base for most commercial chili powders (McCormicks, Durkee etc.), which are actually a mixture of several ingredients.
Pretty mild. Only 3,000 units as compared to a jap at about 25,000.
From the link above:
Ground Ancho Chili Pepper
Ancho pepper is the most popular chili pepper for Mexican cooking. They are not hot, just richly flavorful with a beautiful purple color. From New Mexico.
To make your own chili powder: Start with 3 TB. ground Ancho, add 1 tsp. cumin and Mexican oregano, along with garlic, onion and hot peppers to taste. Use 1-2 TB. per quart of chili.