P designed his own tumbling machines. Reversing the direction of the drum's rotation was a dangerous task. The motor that turned the drum was controlled by a switch manufactured by D. P had connected the switch to the motor by using three wires with insulated 'alligator clips' on the ends. In order to reverse the direction of the machine, the operator was required to disconnect two of the alligator clips from the motor by hand and reverse them. For obvious reasons, it was important for the operator to make sure that the switch was in the 'off' position before disconnecting the wires from the motor. P was electrocuted and died. Ps claimed that D’s switch was defectively designed because it had a large 'phantom zone' that sometimes made the switch appear to be 'off' when it was actually 'on.' Eventually, D moved for summary judgment on the issue of causation. It was granted and affirmed by the appellate court. P appealed once again.