otomobil/Shutterstock Twist-off gas caps — a feature that's becoming increasingly rare in modern cars – are slowly being replaced by capless fillers after Ford introduced the technology in the early 2000s with its GT sports car. While the GT served as a low-volume testbed influenced by the Blue Oval's NASCAR endeavors, mainstream adoption came with its use in the 2008 Ford Explorer and Mercury Mountaineer. Ford marketed the capless system as Easy Fuel, and the technology eventually caught on, with other manufacturers such as General Motors, Stellantis, and Honda adopting similar systems. Ford's Easy Fuel mantra was simple — make fueling as easy as possible while making it difficult to get fuel out. With twist-off caps, miscreants walking around with a garden hose waiting for the opportune moment could siphon off gas the old-fashioned way, but Easy Fuel was designed to make that harder, not easier. Held in place by latches, the spring-loaded trap door opens only when a standard gas-station fuel nozzle is inserted into the filler neck. After refueling, simply remove the nozzle, and the spring forces the flap to return to its closed position. The system is designed so that it won't open when an incorrectly-sized nozzle — like a diesel fuel nozzle — or a generic funnel or plastic hose is inserted, helping prevent theft and misfueling. Other benefits of a capless system include not having to worry about forgetting to screw the cap back on, the embarrassment of it dangling by the side of the car, or it scratching the paint. However, if you want to fill up using a jerry can, you'll need the specific OEM-supplied funnel that came with your vehicle. Theft finds a way? New Africa/Shutterstock So why can't someone just pop over to Autozone and buy one of those funnels, and then proceed with the thievery? Although designs vary across manufacturers, modern cars have anti-siphon valves, screens, and other failsafes to deter fuel theft. However, that hasn't stopped creative folks from breaking out their ingenuity and stealing fuel. Rising gas prices have led the desperate ones to bypass these anti-theft fuel setups with varying levels of intelligence, according to The Washington Post. In the case of Tasi Malala, an unfortunate resident of Scottsdale, Arizona, the thief not only made off with his fuel but also drilled a hole in the truck's gas tank, leaving Malala with a $3,000 repair bill. This form of theft is becoming increasingly popular these days. While you can't necessarily blame capless fuel fillers in such situations, there are other scenarios where they can cause problems. Like when you find someone stranded on the road and genuinely want to help by lending them some fuel. Or maybe there's heavy snowfall and a power outage, and the empty emergency generator could be useful, if only you could siphon some fuel from your car. You may stumble across other practical issues, like dust ingress and frozen flaps, according to GM Authority. The convenience and anti-theft logic are welcome, though. Love them or hate them, capless fuel fillers seem to be the way forward for internal-combustion cars.