Here is a Slotvent UPVC double glazing window trickle air vent is a plastic air vent . Designed specifically for UPVC window frames. It features awhite finish and is suitable for adding ventilation to UPVC windows. The brand, Slotvent, ensures quality and durability in this essential home improvement. In good condition,there is a separation in the grill but does not effect the operation of the vent.
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