Upright Damper Spring Tension Tool – this is a gravity based, calibrated weight spring hook with a special-made hook, used to regulate consistent tension of the damper springs.The procedure is performed with the action removed and positioned horizontally in an action support cradle. This factory-based tool is specifically weighted for Bass damper and Treble damper tension (used with or without the end cap) according to common tension scales, and works on a go-no go visual indication. The tool is held only by the slip ring and vertically positioned with the hook resting on the damper wire just in front of the wood damper lever. If the weight of the tool does not make the damper lever drop at all, spring tension is too strong. If the damper lever drops, then spring tension is too weak. Weaken or strengthen the damper spring by opening or closing the coil until the damper tool makes the lever just wink without dropping. The procedure is quick and accurate, and with practice allows feathering of the tension for a smooth transition into the treble.