Combination ? Triples doubles ?

"Combination Vehicles" is the Class A written test. So yes, you need that.

"Doubles/Triples" is a separate test for an endorsement.

 

The combination endorsement allows you to drive a commercial motor vehicle (CMV) with a trailer attached. The combination endorsement is required for a Class A CDL and allows only one trailer to be attached to the power unit.

 

YES, those others are just "written" tests, not driving tests

 

In my state and probably all states to have a CDL-A you need to pass written/computer tests for General Knowledge, Combination, and Air-Brakes. Combination refers to a truck that pulls a trailer that can be disconnected instead of a straight truck, where the freight box or bed is permanently connected to the truck. If you don't take/pass the Combination test you are restricted to driving a straight truck.

Doubles/Triples is one other written/computer test you can choose to add to your CDL so that you can pull a set of trailers (2 or 3) connected to your truck.

Unless you have a particular job in mind and never want to pull trailers with your commercial license, you need to pass Combination. If you don't know what you want to do in trucking I recommend every student pass Doubles/Triples, Tanker, and HazMat in addition to the General, Combination, Air Brakes almost all CDL students get. HazMat may be the exception. It adds about $150-200 to the cost of the CDL and you may have to make at least 2 trips to the driver license office to complete it or renew it. There are plenty of good jobs where HazMat is never necessary.