Hi Folks, I'm new here with my first Colt revolver. Its a 1931 Detective Special, serial #4034XX, nickel plated. I'm curious if anyone knows the significance of the letter "K" inscribed directly underneath the serial number. Also, I've noticed that all other DS's have the colt insignia engraved just above the stock handle grip on the left side of the gun, but mine does NOT have this insignia. Any thoughts?