Thai: พริกเหลือง (prik leung)
Orange chilies are spicy, but not as spicy as prik kee nuu. They have a lot of flavor too. Orange chilies are used most often in “Pad Phet”. Buying these outside Thailand may be difficult. You can substitute with prik kee nuu, but the taste will be different.
Storage: You can store chilies sealed in the refrigerator, or frozen in the freezer. I tend to buy a bunch and freeze them, as I don’t notice much difference in flavor, and they last forever.