Abstract: In combination with a telescoping well mast structure having a fixed lower structure and a traveling upper structure, a device to time and actuate the extension and retraction of a racking platform pivotally attached to the upper structure. The device comprises at least one pulley secured within the upper derrick structure adjacent the crown and at least one lower pulley secured within the upper structure adjacent the lower end thereof. At least one cable extends from the platform around the upper pulley, the lower pulley and to a wheeled trolley adapted to travel along a portion of the lower structure. When the upper structure is extended the wheeled trolley is propelled along the lower structure by a pushing member on the upper structure until received into a catch housing on the upper portion of the lower structure. Once the wheeled trolley is restrained by the housing continued extension of the upper structure allows for the racking platform to extend by means of gravity.