What kind of warranty is often offered not through the manufacturer but instead through a third party?

Answer: Extended warranty

Explanation:

Extended warranty is the service insurance or contract that is offered to any individual apart from the standard warranty as an addition. It acts as the warranty which can run for longer period of time which is offered by a third party.

This warrant costs extra besides the normal warranty that is provided for any unpredictable and expensive repairing work. It provides warranty to cars, bikes etc. which can be purchased by the consumer as per their will.