A Peter Paul Rubens sketch owned by heirs to the Royal Philips Electronics NV fortune sold for 3.4 million pounds ($6.9 million) before fees at a London auction tonight. The Rubens oil sketch "Two Studies of a Young Man" went to a single bidder on the telephone and failed to make its low estimate. The work was estimated to sell at 4 million pounds to 6 million pounds by Christie's International, which promised the Philips family a minimum price whether the work sold or not. The Rubens was the most expensive item in a week of Old Master auctions in the U.K. capital. "My job was to get the best deal for my clients," said Johan Bosch van Rosenthal, an Amsterdam-based art adviser to the Philips family, in an interview before the sale. Christie's sale on King Street, which is still going on, is valued at 24.8 million pounds to 36.7 million pounds, including the Philips collection at 8 million pounds to 12 million pounds. Rubens's study, showing front and side images of a young man's face, was made in Antwerp around 1615 and was a model for the artist's image of Balthasar in "Adoration of the Magi," which hangs in France's Musee des Beaux-Arts de Lyon, according to a scholar cited by Christie's sale catalog. Christie's sold the sketch for 1,560 pounds in 1934. Anton Philips, the electronics company's founder, probably bought it soon after at about the same price, equivalent to about 76,000 pounds today, adjusted for inflation, said Christie's. Royal Philips Electronics, Europe's largest maker of televisions, was founded by Anton and his brother Gerard in 1891 to make light bulbs. Five Didn't SellFive out of 16 Philips pictures failed to sell, including Aelbert Cuyp's ``A Landscape With Cattle Grazing on a Bank,'' with a top estimate of 1.5 million pounds. Another five, including the Rubens, sold below their low estimates, indicating Christie's may not have done well with its guarantees. "I don't like to see anyone lose money, but for the family the guarantees were a good deal," said Bosch van Rosenthal, after the 16 lots were offered. "The prices are high for the Philips pictures," said London dealer Johnny Van Haeften, in an interview before the sale.