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Sound attenuating air transfer unit for large air flows

The transfer units CTK and CTM have been developed for today’s increasing demands for low crosstalk between rooms The combination of small open free area and angle changes give very good sound reduction at a low pressure drop.

  • For transfer air through walls or wall/ceiling
  • Meets cross-talk requirements in standard buildings
  • Large flow area up to 220 l/s
  • Square hole
  • Type approved sound attenuation material CLEANOLON® -AL
  • Easy installation
  • Standard colour White RAL 9003
    • 5 alternative standard colours
    • Other colours upon request

Technical specifications


Hole in suspended ceiling  l/s Hole in suspended ceiling  l/s
  10 Pa 20 Pa   10 Pa 20 Pa
150 43 60 300 x 150 28 40
200 78 110 500 x 150 71 100
300 155 220 800 x 200 142 200

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Document Article Document type Size Format Download
Sound attenuating transfer unit CTKb ProductSheet 338.41kB pdf
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