Mike Phillips' How to use the Flex XC3401 VRG Dual Action Orbital Polisher Paperback Book In the How to use the Flex XC3401 VRG Dual Action Orbital Polisher book, Mike Phillips provides an in-depth look at the lean, mean, German-made paint correction machine known as the FLEX XC3401. 52 pages. Full color images. Step-by-step instructions.