What is gp thinner?

GP thinner, short for general-purpose thinner, is a solvent used to dilute or thin paints, varnishes, and other coatings to achieve the desired viscosity for application. It typically consists of a blend of organic solvents, such as mineral spirits or turpentine, which help improve the flow and leveling of the material being used. GP thinner can also be used for cleaning brushes and other painting tools. It's important to use it in a well-ventilated area due to its potentially harmful fumes.