The sensors in this package took the prize for being the biggest in our test and looked clumsy compared to some of the other systems, although a hole saw was provided for easy fitting. The red display was clear, but reminiscent of a Seventies watch, and the single tone beep, which kicked in at 30cm, could have been louder. It took a while for it to see the bollard, not detecting it until 60cm away, and it didn't spotthe bicycle until our car's bumper was over the handlebars.