Maradyne MC109K Challenger Series 10" 90W Reversible S-Blade Fan. At Maradyne we design only the highest quality components into our fan assemblies. All plastic components are molded from engineering grade glass filled nylon resin. All motors are designed for long life, high durability and use in harsh environments. These motors perform exceptionally well on the track and in extreme off-road conditions. All fan products are performance tested using our in house air test chamber which insures you can trust our performance numbers. Maradyne engineering also controls and monitors the design and manufacture of our fan assemblies at every step of the process, insuring you get quality product everytime. Maradyne engineering strives to improve upon existing industry accepted designs so you get the best fan for your buck. Maradyne fans are found on NASCAR cars & trucks, dragsters, hot rods, off-road vehicles, mobile generator sets, military vehicles, buses, golf carts, and many other specialty applications.