To ensure that a torque wrench is accurate, it’s necessary to check the calibration of the wrench before use. Typically, users can calibrate torque wrench accuracy to within ±4 percent ...

As the saying goes, you buy a good tool once, but you pay for a cheap one every time you use it. CDI Torque is owned by Snap-On, and there's a lot of the same DNA in the Snap-On torque wrenches.