BGNing Aluminum 1/4-20 Male to M6-1 Female Adapter Screw Head Tripod Adapter Screw Photography Accessory with Reinforced Side Hole D15 20mm. a, 1/4-20 7 revolution M6-1 7 female adapter screw, used to adapt 1/4-20 screw hole to M6-1 screw hole or M6-1 screw.
eBay