visor for racehorses

Question

visor   hello sir, visor is a small slit at the back of blinker cup which encourages the horse to have an idea of compitition coming from behind. may i know how should the rider to get know that a horse requires a visor if it is not improving with blinkers?

Answer
If the horse suddenly surges when a horse comes in sight or hesitates to move up until a challenger appears, then it may be a good idea to cut holes, or as we call them in the US, peepers, in the back of the blinker cup. It may be something you may have to experiment with to see if it help performance or not.