Double Thread Female to Female Bolt Screw Reducer Fitting Adapter. These female thread adapter are useful where thread size of screw needs to be reduced or increased. Thread pitch 0.5mm(M3 )/0.7mm(M4 ) / 0.8mm(M5 ) / 1mm(M6 ) / 1.25mm(M8 )/1.5mm(M10 ) / 1.75mm(M12 )/ 2mm(M14 ) / 2mm(M16 )/2.5mm（M20 ）.
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