broda 30VT Mode D'emploi page 22

Note: When adjusting cylinders with tools that come
in contact with the cylinder rods, a cloth or some other
protective material must be used to protect the sliding
surface of the rod.If the rod becomes scratched or
marred it will damage the seal on the cylinder and the
cylinder will fail.
Damaging a cylinder in this fashion voids the
manufacturer's warranty.
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