3 Legged Thing Dual Threaded Big Bootz. Durable rubber over stainless steel 1/4" thread, with 3/8" sleeve adapter for ultimate compatibility. Suitable for almost all terrains and surfaces. These Bootz are compatible with any tripod with a 1/4"-20 or 3/8"-16 thread. These can also be purchased as spare replacements for your 3 Legged Thing Mike, Nicky or Tommy tripod.