Sold in bags of 4 2 needed for each sash jammer Supplied with machine screws to suit We recommend using Jack Nuts to gain a secure fit of Sash Jammers onto un-reinforced window frames. You will not know if your window is reinforced until you drill into it and feel the tension. For this reason we recommend purchasing jack nuts with your order. If your window is steel reinforced please use the uPVC screws we provide. We will provide online fitting instructions with your sash jammers order Using A 9.5mm drill is recommended when using jack nuts .
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