This is the listing on found on Gunsamerica.com for this revolver one of a kind...interesting write up. Seems it was a prototype that got out of the factory by mistake.
Taurus .40 Prototype Revolver 4138 Only One Ever Made Hard Chrome 2 in. Mint in Box
1 available
SELLER NAME robertsontradingpost
SELLER STOCK # HG0979
CATEGORY Taurus Pistols/Revolvers > Revolvers
CONDITION Used - See Item Description.
Price: $889.95
We always pounce on Tauruses, especially discontinued and pre-1990 Tauruses not only because they’re fine firearms; we and a good many others consider them eminently desirable and even collectable. This revolver came from a recent Miami factory sale of factory reconditioned Taurus firearms that are so marked on their boxes. It is definitely covered by Taurus’s Life Time Repair Policy. The only detractions that we detect to this revolver are light cylinder rotation marking, light amounts of residue in its bore and chambers from recent test firing at the Miami Taurus Plant, and an X Suffix beside its 8-digit serial number. The box on this one is mis-marked for a .41 Magnum, yet the serial number on the box is correct. This .40 S&W Caliber Medium Frame Taurus is a 5-shot capacity snub. It comes with an instruction manual, uncompleted warranty registration card, and two keys for its built-in hammer lock. This is a prototype revolver that Taurus never marketed. Note the beautiful Hard Chrome Finish – we assume that the final C in the product code designates Hard Chrome – especially on the hammer and trigger, most pleasing to many of us S&W traditionalists. This is, we are quite sure, a rare Taurus. Unlike its rather outlandishly-furnished predecessors by Charter and Smith & Wesson who either had to use rimmed ammo as the Charter Pit Bull did; or a strange ejector assembly, as with the 547 Smith & Wesson, this Taurus’s cylinder chambers are simply recessed and use a moon clip, so that a person can have several instant speedloaders on hand. While we don’t have any of the moon clips at press time, we are making efforts to determine whether a Smith & Wesson 610 loader will work. This revolver weighs in at 29.5 ounces empty. Even though its barrel isn’t ported, with the ribbed factory rubber grips and weight, a person could have pleasant, economic shooting and plenty of confidence with this fine Taurus. After one of our friends called Taurus International about moon clips, we got a rather interesting call from Salesman Richard C., who may bear responsibility for allowing this revolver to leave the Miami Plant. Richard threatened to call the BATF and, strangely, the Credit Bureau if we did not return this revolver. Own this unique collectable Taurus 4138, the only one on the market, for only $ 889.95
Hope they make it a production item.