Horse and saddle, electric eye timer, and three 55-gallon drums
To have the fastest time in the event with no penalties. The barrel racer will enter the arena, usually at full speed and cross the start / finish line triggering an electronic eye that starts the clock. The contestant will direct her horse to complete a cloverleaf pattern (one right turn and two left turns OR one left turn and two right turns) around three barrels positioned in the arena, then race back across the start / finish line, tripping the eye and stopping the clock. You will usually see contestants beginning with the right barrel.
The contestant deviates from the cloverleaf pattern in any form.
The contestant can touch or even move the barrels from their original position, but will receive a five second penalty for each barrel knocked over. Even one barrel overturned usually spells a long trip home with only your applause as consolation.