Joiner screws are used for furniture, for example whether the kitchen cabinets, shelving for nonviolent, bedroom units, office units, desks, wood panels. - M4 x 30-40 MM. - M6 x 30-40 MM. You need to drill hole Ø 5 mm in 2 panels/boards, then assembly longer part of joiner screw (female) and screw shorter part (male) into it to connect 2 panels/units/cabinets.
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