Oster 4961 Ice Blade
This Revolutionary Ice Crusher stainless steel blade acceosry is probably the most important tool to make an Osterizer blender operate at its fullest capacity. The ingredients are pulverized as they are pulled down toward the extremely shart rotating  blades that is run by the one and only All metal drive designed by Oster.  Also packed in with the blade is a rubber sealing ring that eliminates leaking from teh jar.