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Practice quizzes / NJ CDL Air Brakes Test Practice Questions - New Jersey Commercial Driver License (CDL) Air Brakes Knowledge Test Exam / Question 147818
Practice question

On the New Jersey CDL Air Brakes knowledge test, what is the shape and color of the trailer air supply control on a tractor?

  1. A yellow diamond knob
  2. A red 8-sided (octagonal) knob
  3. A blue triangular knob
  4. A green round knob

Answer: B — A red 8-sided (octagonal) knob

The correct answer is shown above. Try the full quiz for additional practice.

Practice more: NJ CDL Air Brakes Test Practice Questions - New Jersey Commercial Driver License (CDL) Air Brakes Knowledge Test Exam →
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