B&M SuperCoolers are 100 Percent aluminum construction and use stamped plates sandwiched together to create one of the most efficient oil cooling devices available. Not only does this unique design provide for maximized cooling through more efficient heat dissipation but it also provides a much sturdier cooler which is practically impervious to flying rocks or other debris. The Super-Coolers intended for automatic transmission fluid also offer an additional feature known as "Low Pressure Drop". The coolers assembled with hose barb ends include a unique bypass feature allowing a controlled amount of ATF to bypass the stacked plate core when the fluid is cold. This is beneficial in cold climate areas to guard against lube system failure. Controlled by viscosity, fluid is returned directly to the lube circuit through bypass openings in the stacked plate core. As the temperature increases, more ATF is directed through the core. This highly efficient design combines improved protection against lube system failure with the required levels of optimal heat transfer.