Strong, self-lubricating black Delrin ground throws with external cam for strength and maximum throw. Molded on pin for direct mounting. All 100 series (Rigid) stands require modelers to fabricate a spring connecting link between the stand and the turnout. All 200 series units (Sprung) have internal springs so they can be connected directly to the turnout throwbar. Measurements indicate the maximum amount of side-to-side travel when the lever is thrown.