JLG 4017 Operator Manual - Manual (Page 31)

Section 2 - Pre-Operation and Controls
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2.3 OPERATOR CAB
The telehandler is equipped with an enclosed FOPS/ROPS cab.
WARNING
Never operate telehandler unless the overhead guard and cab structure are in
good condition. Any modification to this machine must be approved by JLG to
assure compliance with FOPS/ROPS certification for this cab/machine
configuration. If damaged, the CAB CANNOT BE REPAIRED. It must be
REPLACED.