Park's patent driving cleek, so stamped on the back of its blade, has a low profile blade and distinctly rounded back. This was done to concentrate the weight directly behind the ball, directly opposite of where the ball would be struck.  

Park never actually received a patent for this club, but the auctioneer suspects he applied for it on July 9, 1890. At that time he applied for a British patent (10575) to cover "metal golf clubs."  He later abandoned this application.  This makes even more sense given that Park applied for a patent on his lofter just over a year earlier, on March 23, 1889. That club met with a bit of success, so why not come back and patent another iron? Of course! But what more than a few early clubmakers figured out was this: 

If they simply applied for the patent, they were issued a patent application number which would become the actual patent number when the patent was completed. So they would simply use the number or acknowledge the patent on their special club but never actually spend the money to complete the application. Nobody else would be issued that number in the year the application was taken out.  Plus the competition was not given to looking up the patent to see if one was actually issued. Besides, many patented golf clubs turned out to be money losers for the patent owners. 

This club has its 38 1/2" original shaft and sheepskin grip. The shaft is stamped "Wm Park". Overall, this is a very nice, all original club made by the 1887 and 1889 British Open champion.