Patent ID: 8015806

Claim:
An apparatus for treating an exhaust gas from an internal combustion engine, the apparatus comprising: an exhaust pipe to be connected to the internal combustion engine; at least two modules to be connected to said exhaust pipe for exhaust-gas treatment; and at least one connecting device, associated with at least one of said modules, for connecting said at least one module to said exhaust pipe to cause at least part of the exhaust gas to flow through said at least one module, said at least one connecting device being configured for permitting the exhaust gas to flow through said module associated therewith while excluding at least one further module from the exhaust-gas flow; each said at least one connecting device being configured to be movable between: a first position to produce a connection to a respective one of said modules through which a fluid can flow, a second position to disconnect a connection to said respective one of said modules through which a fluid can flow, and a third position to prevent flow through others of said modules; and said at least one connecting device numbering one fewer than said at least two modules.