The flour is wet, rolled out into thin, round sheets and put on bamboo mats to dry. They look a bit like flour tortillas, though they are very brittle.
They are sold in packages.
To use, soak in hot water for 20 to 30 minutes, then boil or steam for 5 minutes to heat and rinse under cold water. They are usually cut into small squares or shredded into strips and incorporated into a dish as a noodle. Or, once rehydrated, they can be used as a wrap for ingredients such as shrimp or ground shrimp, then deep fried.
Called “fun pei” in Chinese.