Offered here is a circa 1906 Willie Dunn Jr. patent "Pyralin" Duplex wood by The Kempshall Manufacturing Co. According to Jeff Ellis, Dunn's patent described the vulcanized rubber pyralin head as "virtually indestructible." It could be used right or left handed, which made it an early version of a rescue club. According to Ellis, this example is one of only two Kempshall pyralin duplex clubs known to exist. 

This club originates from the famed Jeff Ellis Collection, and was featured in his book The Clubmaker's Art (TCA 1, p. 415; TCA 2, p. 518).