Rolls-Royce considered offering a more exclusive, long-wheelbase Phantom VII model based on the Silver Shadow, but production was not pursued and no prototypes were built. Instead, a long-wheelbase variant, some 4 inches longer to provide additional rear seat legroom, was offered in the United States from May 1969, and available to domestic customers from early 1970. A pilot series of ten long wheelbase cars had been built in 1967 and sold, one of them to Princess Margaret. Some long-wheelbase models were fitted with a privacy glass divider. Outside of North America, the cars with a divider were fitted with a separate air conditioning unit mounted in the boot - North American safety laws made this impossible, as the petrol tank would have had to be relocated. The cars with a divider lost the entire gain in wheelbase. The glass divider was electrically retractable.