high viz

[Grahamm]

As for flashing lights, they'd be a disaster - very hard to judge how far away they are.

Yep, they generally work for bicycles in town because they're never going to be far away, but one time I was riding down the A32 (past the Timber Yard for those familiar with it) and there's a long straight.

I was planning an overtake, but up ahead I could see one of those very bright flashing cycle lamps (even I, as cyclist, think they're too bright and have too wide a spread of light).

It turned out that it had been so far away that I could easily have made the overtake,  but because all I could see was the lamp I had no idea exactly how far away it was, so had to give up on the overtake.