That’s a brand-name and it’s technically more accurate to refer to it as a “screw-in mooring. A screw-in mooring consists of a galvanized shaft with various round plates designed to hold the “screw” into the substrate. Advantages of this type of system include reduced need for scope on the mooring rode and therefore reduced scouring of the substrate. In locations where the substrate consists of fine sediments or organic mud, the use of several extensions may be necessary to achieve desired holding power. It is possible that substrate conditions may be so extreme that use of this system is impractical. Screw-in moorings are installed and annually maintained by a professional diver or specially-designed barge. -Dawson Farber