2024 ND CDL Practice Test: Class A - Test 6
Based on
2024 ND CDL Handbook
4. What is the purpose of dummy coupler?
A
Dummy couplers have no purpose. This is a name for couplers that are no longer working.
B
Compress air.
C
Protect the air hoses from rubbing together.
D
Prevent water and dirt from entering into the coupler and air lines.