Rocotillo Chiles look like miniature bell peppers with black seeds inside.
They are very small, only about 1 inch (2 ½ cm) tall, and grow in clusters that ripen from green to orange to red.
They have a fruity taste, but despite being related to habenero chiles, are not very hot.
Estimates of their hotness in Scoville Units range from 1,000 to 2,500, depending on the conditions under which the chiles were grown.
Substitutes
Another mild chile with just a bit of kick.