Product Name : Hex Standoff Spacer;Thread Dia (A) : (M4) 4mm Male to FemaleMale Thread Length(B) : 6mm/ 0.24";HexagonPillar Length(L) : 25mm/ 1"Hex SideWidth(C) : 7mm/ 0.28";Total Length : 31mm/ 1.2"Nylon material, single hex head, male female type threaded, and it is good for mounting between PCB circuit boards and machine boards.