Offered here is the incredibly rare circa 1923 Holmac Rudder Putter. According to Jeff Ellis' book, The Clubmaker's Art, Ellis was only able to locate 5 authentic examples.

"The Rudder Putter had a very limited life span. It was already illegal before it was offered!" (The Clubmaker's Art, 2nd Edition, p. 544). Established R&A and USGA rules already deemed illegal any club that has a "measurement across the face of any club had to be longer than the measurement from the face to the back of the head." Whether the club's producer knew this or not is unclear, though very few were ever made.