The 311 Series Double-Acting Wiper is a popular upgrade to the traditional singlelip wiper designs. It offers enhanced performance and can be easily retrofitted into existing wiper grooves. The double acting design ensures maximum resistance to contamination, while working in tandem with the rod seal to maximize performance. The internal wiping lip is notched to prevent pressure trapping between the wiper and the rod seal. The wiper is designed to exclude and protect the hydraulic cylinder in the harshest conditions.