Review on Enhance Your Cycling Performance with Origin8 HUB OR8 Single SPD KIT for F-HUB ALY 09 RD by Andre Pendergrass

. There are Shimano freewheel hubs that these seals will not fit. For example Shimano FH-7800. The freewheel housing part code is Y-3B9 90200. Technical documentation can be found on the Shimano website. I also found it from this link: http://si.shimano.com/php/download.php?file=pdf/ev/EV-WH-7800-R-2257.pdf Look at part number 12 in this PDF on. File. You will see that there is a small step of a few millimeters on the body that prevents these pads from sliding all the way onto the cassette. I am also attaching a picture of this hub shell so you can see what it actually looks like. I don't know if there are other Shimano hubs that are built like this. If you have this type of hub body these spacers will not work as the diameter of each one is not large enough to overcome this step. It is very important that you check this before purchasing these pads. Otherwise you will have to buy a new bushing or send it back.