Chapter 4  Angular Measurements
Angular Position Measurements
Measurements Reference Guide 4-71
Clutch breakaway nut
If the clutch breakaway-nut breaks, order a replacement clutch 
breakaway-nut (Agilent part number 55290-67002).
CAUTION To prevent damage to your machine or the measurement apparatus, do 
not use any other type of device in place of the clutch breakaway-nut. 
The clutch breakaway-nut O-ring is provided as a reminder to loosen the 
clutch breakaway-nut before you make a measurement. It does not 
contribute to the strength of the breakaway nut itself. If the O-ring breaks 
or is lost, you may continue to use the breakaway nut. The O-ring is not 
separately replaceable; it is supplied as part of the clutch breakaway-nut 
(Agilent part number 55290-67002).