Question: Is this just for curls and or can you straighten as well?
Answer: The Salon One-Step Hair Dryer & Volumizer is for a smoother look.
Question: What is the plug?
Answer: US/UK/ER/AU I have shoulder length hair & it dried pretty quickly. Love this dryer!
Question: how big is the barrel of this brush?
Answer: It is around 2 to 3 inches. It is oval shaped not round.