These bulbs have in-line locating/bayonet pins, so they will fit in place of the standard clear (white light) 12v 21w bulbs that were fitted to almost all cars up to the mid-90s.
They are not suitable for most modern cars which require bulbs with offset bayonet pins.
NB: We have replacement indicators with clear or orange lenses, for 2CV front, 2CV Van front & rear, and DS Estate rear.