years, but the obtrusive appearance of the rails and their blocking of the car's rear wheels when sliding through corners were powerful disadvantages. New clubs increasingly chose the slot system. By 1963, even the pioneer rail-racing clubs had begun to switch to slots. In 1957, Minimodels (UK) converted its Scalex 1:30 (later, 1:32) clockwork racers to electricity, creating the famous Scalextric line of slot-guided models, and Victory Industries (UK) introduced the VIP line, both companies eventually using the new plastic-molding technologies to provide controllable slot racers with authentic bodies in 1:32 scale for the mass market. Both lines included versatile sectional track for the home racer - or the home motorist; VIP produced sports cars and accessories slanted toward a "model roadways" theme, while Scalextric more successfully focused on Grand Prix racing. As Scalextric became an instant hit, American hobbyists and manufacturers were adapting 1:24 car models to slots, and British-American engineer Derek Brand developed a tiny vibrator motor small enough to power model cars roughly in scale with HO and OO electric trains. In 1959, Playcraft division of Mettoy produced these in the UK, and a year later, Aurora Plastics Corp. released HO vibrator sets with huge success in the USA. The tiny cars fascinated the public, and their cost and space requirements were better suited to the average consumer than the larger scales. In only a year or two, Scalextric's 1:32 cars and Aurora's "Model Motoring" HO line had set off the "slot car craze" of the 1960s. The slot car craze was largely a US phenomenon, but, commercially, it was a huge one. In 1963, after a million and a half had been produced, Aurora replaced the trouble-prone vibrator cars with an innovative flat-commutator ("pancake") motor, also created by Brand, and what is probably the best-selling slot car in history, the Aurora Thunderjet-500 was born. Faller (Germany) produced it for sale in Europe, and competing companies tried in vain to match the speed and reliability of Brand's design. The Thunderjets and their improved versions, the AFX, sold in the tens of millions, completely dominating the HO market for almost a decade, until challenged by the Tyco cars in the early 1970s. By the late 1970s the slot car boom was well over, the model train tie-ins and miniature motoring concepts largely forgotten, and the market returned to the more serious racing hobbyist, with local and national racing