[3] Sound of Seil was built by Cammell Laird of Birkenhead.

[3] They have a single car deck with 194 lane-metres between bow and stern ramps.

The ferries use LED lighting and enhanced heat recovery.

Along with up to three other vessels, Sound of Seil operates Western Ferries' Clyde service between McInroy's Point (Gourock) and Hunters Quay (Dunoon).

This 2.2 nautical mile crossing[2] allows vehicles to avoid the A83 "Rest and be thankful".