Tin whiskers are formed when thin single crystals of tin grow spontaneously from a tinned surface. These have caused electrical shorts, particularly in parts which have been Electrotinned. Under accelerated conditions researchers have been able to grow whiskers up to 200-in long from Electrotinned surfaces. They were unable to find such whiskers, after the same inducement, on Commercial Hot Dipped Tin, Air Leveled Tin, or Reflow Tin. It is theorized that for Reflow Tin, any stresses from the electroplate (that can cause whiskers) are eliminated by the remelting of the tin. There is no such source of stress for Commercial Hot Dipped Tin and Air Leveled Tin; they were whisker free as expected.