Manufacturers of Detailing related products
Orange peel is the term for the unevenness of a layer of paint on top of a surface. When you look closely, the surface resembles the skin of an orange. Many detailers consider orange peel unwanted, ugly and a fault of the painter. Orange peel can be found in the clear coat and also in the colored layer of paint.
A Paint Thickness Gauge (often abbreviated to PTG, and also called a Paint Depth Gauge) is an electronic device that measures the distance between the body-panel and the sensor. This way you can measure the thickness of the paint. This gives you an indication of how much paint you have left to work with.