Helix anchors derive their holding from the soils into which they are screwed. The Square Shaft anchors are installed with the aid of hydraulics to screw the anchor through resisting soils. The anchors have been repeatedly tested by Mother Nature and tugboats with load measuring equipment.
 

The results of the first test (performed in Vineyard Haven, Massachusetts, under the watchful eye of area harbor masters, a marine industry reporter, and a representative of Boat/US) are typical of all the load tests performed.