PB – The Causes of Hair Growth(KCBT) You must first complete PB – What Are Precision brows?(KCBT) before viewing this LessonPlease sign up for the course before starting the lesson. PB - Structure and Functions of the skin(KCBT) PB - Health and safety(KCBT) Back to: Precision Brows Course(KCBT) > PB - Manual (KCBT)