These products are designed to install polyethylene ducting using a screw-in tapered thread to grip the inside diameter of the duct. The pulling eyes are typically used to install innerduct inside a larger duct. These pulling eyes are designed with cutting edges to actually cut a thread in the bore of the ducting as it is being screwed in, much the same way as using a tap to cut a thread in steel. This helps to ensure a reliable grip. Installation typically requires only seven or eight full threads of contact to give a grip stronger than the ducting itself. The pulling eyes are installed quickly and easily and require no special tooling. They are manufactured out of steel and plated for durability and corrosion resistance. This product is similar to the Lug and Clevis series, but incorporates a built-in swivel head. These should only be used to install innerduct and are not suitable for use in any kind of directional drilling application.