Walraven 2154039041 is a WM Pacifyre MKII fire-protection collar for plastic pipe with outside diameter 39-41 mm. The intumescent liner expands under heat to seal the aperture as the pipe softens, restoring the fire-resistance rating of walls and floors. The self-extinguishing grey housing is 65 mm wide and 205 m long, insulating and vulcanising in place. Typical application is passive fire-stopping of PVC, PP and PE waste and vent stacks at compartment boundaries.