What kind of pistol did Elvis Presley carry in his boot?

A small pistol that Elvis Presley at one time carried in his boot was a .25 ACP Semi-Automatic Pistol. The firearm was a Wischo-KG Erlangen Model 11 Serial number 32704, .25 caliber (6.35 mm) semi-automatic gun marked on the barrel with “SM” and “Made in Germany”.

The pistol was sold at auction at Graceland in Memphis, TN on October 2016. At the time, the firearm was offered with a notarized letter from Richard H. Grob, Elvis’ bodyguard from 1967 to 1977. In the letter from Richard, he describes in detail their (Elvis' and his) shared passion for firearms. He points out the enjoyment they experienced in discussing, practising, and purchasing firearms together. Richard further mentions how he obtained the pistol from Elvis, who told him, "It's too small a weapon to be very effective." This diminutive pistol only measures 3 1/4 by 4 1/2 inches (8.21 x 11.43 cm).