What type of equipment is prohibited on a private vehicle?

The correct answer indicates that none of the specified types of equipment are prohibited on a private vehicle.

In many jurisdictions, including Hawaii, certain equipment is regulated to ensure safe driving conditions and to prevent confusion on the roadway. A red light displayed on the front of a vehicle could be associated with emergency vehicles; hence, it is typically not allowed on private vehicles as it can mislead other drivers. Bells or exhaust whistles may not be used because they can create unnecessary noise and distractions while driving. Similarly, muffler cut-outs, which might alter the exhaust system to change the sound of the vehicle, can also be prohibited due to noise ordinances or regulations aimed at reducing pollution.

Thus, stating that none of these items are prohibited suggests an understanding that, in general, such items either fall within permissible use or are not explicitly mentioned as restricted in the context given. This reinforces the importance of knowing both the permissible and prohibited equipment for vehicles to maintain safe and lawful operation on the roads.