Butylon is a double-sided tape for sealing nail penetrations through underlays as well as sealing underlays, air barriers or vapour control layers (AVCLs) to both smooth and rough surfaces. Suitable for both internal and external use. Properties Length: 25m. Width: 20mm. Weight: 3kg. Adhesive: double-sided butylon-rubber. Solvent: solvent free. Installation temperature: above 5C. UV stability: 4 months. Shelf life: 2 years at 20C or below. Resistance to ageing: it remains permanently elastic & adhesive. Related products Any klober underlay. Wallint 50 or Wallint Solar vapour control layers & air barriers. Klober Permo Extreme RS SK2 Klober RS SK2 Butylon Tape is a double sided tape for sealing nail penetrations through underlays as well as sealing underlays, air barriers or vapour control layers to both smooth and rough surfaces. Please note the use of this product is essential when laying the Klober Permo Extreme RS SK2 below 15 degrees (and below tempertures of 5 degrees C) as the key primary waterproof barrier. Application Adhering underlays & vapour control layers/air barriers to smooth & rough surfaces. Use below tile battens or counterbattens to seal nail penetrations through the underlay. Both internal & external use.