The Portable Skid Resistance Tester (PSRT) is based on the lzod principle. The pendulum measures the frictional resistance between a rubber slider mounted on the end of a pendulum arm and the test surface. This provides highway engineers or safety engineers with a routine method of checking the resistance of wet and dry surfaces to slipping and skidding, both in the lab and on site. Stanlay India is a manufacturer of Skid Resistance Tester for asphalt/pavement/road friction testing application