Peter Henlein (or Henle or Hele) (1479/1480 – August 1542), was a locksmith and watchmaker from Nuremberg. He is often said to be the inventor of the watch. This is disputed. Henlein was certainly one of the first makers of the watch. Although many say that Henlein invented the mainspring, there are descriptions and two surviving examples show that spring driven clocks had already been made by the early 1400s. He did make improvements to the balance spring, which made it possible to make the watches smaller.