@elliek asks:
Is there a flexible rod sideways out from the seatpost into the road, w/warning flag, the length of the required distance from the cyclists to an overtaking vehicle?
I think my husband's seen one, spring mounted to not cause an accident, but enough to encourage a driver to go farther out to avoid damage to their car.
Q2. Does this exist? Is it legal?
I've seen vertical flags, but that's not what I want. Drivers come too close.