Edgemaster Keychain MyTmite vintage Blue sparkle switchblade knife

Vintage Edgemaster keychain automatic knife made in the late 40s or early 1950s by the Federal Knife Co of Providence, RI and was marketed with the trademark "My-T-mite". They were usually sold from display cards that held 12 knives and sat on store checkout counters. The knife measures 4 1/16 inches open and just under 2.5 inches closed with brass liners and steel button, safety and shackle. The blade is nearly full with patina and scratches and is marked Edgemaster USA PAT PEND. The blue sparkle synthetic scales are in good condition with some shrinkage and scuffs from use. The knife works great with the blade tip seating deep in the well, good snap and good lockup with about 1/32" movement at the tip. Safety does not work, as many did not when new. Good condition, rare color.