Do you have more than one child? Are the two children often only accompanied with one adult on a cycling outing? This extra receiver attaches to your second Child's bike for Cycle Tow Trail-Gator connection. So hey presto buy an extra receiver and then you can easily alternate between children giving them both turns to ride independently or be towed. NOTE: This kit is not required and is only necessary when wishing to alternate between two children’s bicycles with the one adult bike.