The double wall block is attached to the wall of the gas compartment in your mobile catering trailer/van and connects to the gas regulator and the pigtails. It has a W20 inlet x POL outlet.
To go with this double gas wall block you may need to purchase a gas regulator and other gas fittings available on this website.
Looking for a mobile catering trailer or catering van visit www.exceltrailers.co.uk