Combo stud converter adapter screw coupler male/male 1/4" 3/8" & female/female 1/4" 3/8" Desmond brand 2 adapter studs 1 steel stud coupler screw 1/4" male thread and 3/8" male 1 aluminum alloy stud 1/4" female thread and 3/8" female thread multipurpose tripod camera lightstand adapters