This Eberspacher exhaust silencer muffler, is there a specific direction to fit on the pipes please ?

This specific automotive use Eberspacher exhaust silencer can be mounted to allow the exhaust gas to flow in either direction.

Please note though - Not all versions of Eberspacher exhaust silencers are bi-directional so it's always good practice to check your specific silencer to see if there is an arrow embossed on the unit thus denoting direction of intended gas flow