515-024, 520-130, 520-131, 520-132.
The communication mount nut (320-026) should never be tightened using a spanner or other
tool. Tightening the mount nut using a tool will add excessive strain to the parts and could cause damage to the module allowing the module to break free, resulting in flooding of the helmet which could cause injury, or drowning.

Technicians and users of Kirby Morgan helmets are reminded that the communication mount nut, part number 320-026 used on the Kirby Morgan helmets and EXO full face masks should be tightened by hand only. Wrenches or tools should not be used to tighten the module communication mount nut. The mount nut should be installed and tightened by hand only.
For further information, contact your dealer or [email protected]