Remove the frustration of adjusting tension. This measuring device reads the bobbin case thread tension. With easy access to the tension adjustment screw without having to remove the bobbin/bobbin case from the device, the tension on the bobbin case can be adjusted. Adjust the bobbin tension to the same number on the Towa Bobbin Gauge scale with every change of bobbin thread and every bobbin (bobbin case not included)

Instructions in the box demonstrate how to use the gauge, however, don't give recommended readings. Recommended base line for Nolting machines:

• Adjust tension for L-bobbins 100-150,
• Adjust tension for M-bobbins 175-275

Order for the size machine hook, L (small bobbin) or M (big bobbin)