Square shank allows use of wrench or pliers for added torque. Handle marked for easy identification of screwdriver size, type and length. Rugged keystone tip for additional strength. Precision-machined tips for accurate fastener contact. Strong, durable black phosphate tips prevent chipping of plating. Soft, cushioned grip for extra comfort and torque. Exceeds ASME/ANSI specifications. Lifetime limited warranty. Note: This is not an insulated tool.