This gasket is required when replacing an old Ford E4OD transmission pan with a new 4R100 oil pan that has a large drain plug. The gasket is a steel-rubber sandwich with steel washers built into the bolt holes to prevent over-tightening. I installed it very easily, no more leaks I got from the flat neoprene gasket that came with the filter. It may sound expensive, but it's not disposable like it used to be, it's meant to be reused. .