than LHD so the up angle of the cutoff is to the left rather than the right -- some reflectors have notches so the bulb can be installed either way, but most do not. It is just as much a reflector problem as a lens problem though, because of this bulb mounting difference. Marchal used to make regular round 7" lights which worked either way, for people who spent a lot of time on both sides of the English Channel (or in Sweden, until 1967), but that was a long time ago.