Magnetic Tank Bag info, esp. Marssee Marssee Products tank bags (have had mine for three years and I don't know how many miles as its been moved from bike to bike but its a lot) have "capped" magnets. They put a cap of metal over the backside (faceing the bag) that cuts the magnetic field. I will get to a more technical test in a minute but here was my high tech testing method. I placed a video that was in perfect condition in the base of the bag for somewhere in the neighborhood of 21 hours. Played the video. No distortion whatsoever. Now onto the more technical test. Someone in one of the multitude of forums I frequent did a test about a year and a half ago with some equipment he had from work. Now I don't know the terms or the equipment but what he had measures magnetic fields and he related these in numbers. High numbers being strong and low numbers being low. When he did the test on the bottom side of a marsee bag the numbers were as he put it "surprisingly high". Flip the bag over and test there and it was almost unreadable. Almost equivalent to the magnetic field that anything in iron produces (which isn't noticable). The bag has never scratched a tank on any bike I've used it on or done any other damage. The idea that it could shift is rediculous (grab a magnetic tank bag and try to pull it to the side rather than up) and if by chance it did (mine didn't move in a 70 mph game of tree ping pong) the tether is there to keep it in place. ------------------------------------------------------ Chris (H-Man) Pyle