The TranzSporter Secondary Handle Kit by Tie Down Safety is required when using the Solar Panel Saddle Carriage. The saddle carriage blocks the foot pedal, which engages the hoist, so the Secondary Handle Kit allows the operation of the TranzSporter. This TranzSporter ladder hoist part fits on the side of the hoist to engage the motor and carriage. Highly recommended when lifting plywood, solar panels, and insulation panels. This product works with both the TP250 and TP400 models. Tie Down Safety maintains high standards and quality controls using quality raw materials and component parts made in the USA.