W501 module with green substrate and a beige, plastic extraction handle attached by two rivets. Handle reads "DIGITAL EQUIPMENT CORPORATION MAYNARD, MASSACHUSETTS." Reverse side of substrate(with solder joints) reads " SCHMITT TRIGGER W 501F" along the edge. Obverse side has several components and is marked with three inspection stamps and a "C" within a circle; "FLIP CHIP" can be read through substrate, between rivets.
