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Underfloor Horizontal Extension Sleeve

Designed to extend the reach of the underfloor vent for varying cavity and wall leaf widths.

Top Extension Sleeve

Product Code: HD 9660T
140mm long for an outer leaf width of up to 170mm

Bottom Extension Sleeve

Product Code: HD 9660M
155mm long for an inner leaf width of up to 215mm

Downloads

Datasheet

For more info on this product visit our Downloads page

Stand alone photo of the top Horizontal Extension Sleeve

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Hambleside Danelaw’s building products story began in 1976, when an investment opportunity presented itself in the form of a patent for an innovative glass reinforced polymer (GRP) roofing product.

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  • Long March, Daventry,
    Northamptonshire, NN11 4NR

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