6 in 1 personal electric callus removal How to replace the Manicure Roller . Make sure the unit is turned off. Press the release button on the right side of the unit and gently take the Pedi Coarse Roller away. . Place the square shaft of Manicure Roller into the square hole on the left side of the unit. Rotate the roller to make sure the end pad of Manicure Roller aim at the groove of unit. Press the Manicure Roller into the unit until you hear a \"click\"sound. . Inset the micro-manicure kit into the hole on the left side of unit. . Make sure the micro-manicure kit and Manicure Roller are all firmly installed before use. Website: