What characterizes a two-component putty?

A two-component putty is characterized primarily by its polyester-based composition, which requires the addition of a hardener to initiate the curing process. This dual-component system allows the putty to develop strong adhesion and durability once it cures, making it suitable for various applications in automotive refinishing and repair.

The use of a hardener is crucial as it activates a chemical reaction necessary for the putty to set and achieve its final properties. This setting process provides excellent filling capabilities, resilience, and adherence to metal and other substrates, making it a preferred option for repairs that require a robust and long-lasting finish.

In contrast, other choices do not accurately describe the characteristics or behavior of two-component putties. Water-based products do not require a hardener to cure; silicone-based products possess different curing properties and are not typically known for strong adhesion compared to polyester putties; and while some two-component putties can be sanded, they are not necessarily easy to clean with water, as they generally require solvents for cleaning.