The car ferry to Out Skerries is the only one we know of that routinely straps down all vehicles being carried. There's a reason for this: the islands lie beyond the shelter of Shetland's Mainland and the crossing can be bumpy.
The Summer timetable provides a single crossing each way on three days per week, but three crossings each way on three more days each week, meaning that day trips are easily possible if you plan ahead. For full timetable, fare and contact information, check out the ferry area of Shetland Islands Council's website. All journeys to Out Skerries should be booked in advance: sailings only take place if a booking exists.
As with all of Shetland Ferries' services, fares are extremely reasonable, and those charged for the carriage of vehicles especially so. Although Out Skerries only possesses a mile of road, the changeable weather and reasonable vehicle capacity of the ferry mean that taking a car is often a good idea, as it can then be used as a base while exploring the islands.
The vessel used is the Filla. Built in Gdansk and launched in May 2003, she replaced an earlier vessel of the same name on the service. The earlier Filla was renamed the Snolda and took up the Papa Stour service in 2004. The relative youth of the latest Filla shows throughout, whether on the hi-tech bridge or in the exceptionally comfortable and pleasant passenger lounge.