Really Right Stuff's Spike Tripod feet are machined from solid stainless steel, and are designed to dig into soft surfaces to keep your tripod from slipping. These feet are equipped with Accidental Backout Prevention O-rings to keep the feet securely in place and stop accidental loss. These feet are compatible with all of Really Right Stuff's tripods and monopods as well as some other tripods with 3/8"-16 sockets. Features: Machined from solid stainless steelCompatible with all RRS tripods and some other tripods with 3/8"-16 socketsPerfect for soft terrain Really Right Stuff Spike Stainless Steel Single Mono/Tripod Foot TA-3-FS