Top hat collar designed to seal telescopic underfloor vent when gas protection is required. The 1201 top hat is suitable to protect from radon, hydrocarbon, methane and CO2. The preformed mouldings eliminate the need for site fabrication which helps prevent errors. The top hat is easy to handle, flexible, tough, durable and puncture resistant made from medium-density polyethylene (MDPE). Designed to fit Timloc 1201 and 1201XL. The 1201 top hat satisfies all NHBC requirements, is manufactured to BS EN ISO 9001:2015, complies with all relevant building regulations and meets all British Standards.