The 3 legged thing stilettos are designed to be embedded within softer ground to provide an anchor during windy weather and to elevate your tripod off rocky or harmful terrain they are made from stainless steel and each have a 14 20 thread and 38 stainless steel thread making them universally compatible with any tripod that has either of those fittings the stilettos are an essential addition to any photographer wanting to take long exposures or photograph in adverse conditions