Park Tool - TM-1 Spoke Tension Meter
The TM-1 Tension Meter accurately and reliably measures the absolute tension of each of the spokes in a wheel, as well as the relative tension between all the spokes in a wheel. Easy to use and priced affordably, the TM-1 works on nearly any bicycle spoke—no matter what the diameter, material, or shape. The TM-1 is for anyone building or truing wheels, diagnosing wheel problems, or assembling new bikes. It’s a tool that belongs on every workbench.