This is a discontinued version of the MC-31D that was produced several years ago that features a brass washer at the front pivot that adds a nice contrast but is no longer available. Only a few offered here that will go quickly! Mcusta creates custom quality production knives that are hand finished. Machine Custom = Mcusta. Located in Seki, Japan, the company holds an esteemed reputation for producing the finest Japanese folders. This knife features a superior VG-10 core 33 layer damascus steel blade with damascus handles and stainless steel liners. Please note that this version does not come with a nishijin. Stock photos. Mcusta Factory Authorized Dealer.