Dayco?? High Performance V-Belt is the workhorse of the heavy-duty industry. Polyester cord provides maximum power transfer and tension holding capability for the life of the belt. The laminated construction helps absorb greater shock loads associated with diesel engines. These Dayco?? High Performance V-Belt advantages translate into less downtime, lower maintenance costs, and increased dependability. Dayco's High Performance V-Belt meets or exceeds SAE J636 and J637 specifications.