This is a stack of three Motorola 040 CPUs which happened to be included in the large vintage Macintosh collection we purchased off local classifieds earlier this year. The top CPU is the 68LC040 at 33MHz and without an FPU. The two CPUs below this are full 68040 with FPU and rated at 40MHz, though not as visibly clean due to some old heat-sink compound.
