Unior 1693R.2 through Axle Adapter for 1693R 12/15mmProduct features Through axle adaptor is compatible with 1693R series road stands. It enables fixation of bikes with 12 mm or 15 mm through axles. To mount the bicycle on the adaptor, simply remove the wheel from the bike and install the bikes through axle back in to the fork or frame; adaptor then clamps the through axle and secures the bike in place.