Boost your style with the O Rollers that bring on volume in seconds. For short to mid-length hair that's destined for added bounce, ready to use with The O Pod. The O Rollers are available in 5 sizes: 20mm, 30mm, 40mm, 50mm and 60mm. With Induction Heating Technology to heat the O Roller directly. And Cool Touch Technology to heat your hair and not your hand. Get the blow dry look in minutes. The Induction Heating Technology channels the heat directly into the O Roller, heating in just four seconds to create the blow dry look in minutes.