G SCHRADE arched Pullball Onyx scales green ball vintage automatic knife

Geo Schrade Knife Co pullball switchblade with onyx handles made in Bridgeport, CT. This is an earlier knife with the arched G SCHRADE B'PORT, CT stamp and the back of the tang is blank. Can't tell if the dates were ever there, but as nice as the knife is it's not likely that they have worn off, or been removed. The knife measures 2 7/8 inches closed and 5 inches open with brass liners. The blade is full with original finish and stamped as stated above. The Onyx synthetic handles are in nice condition with slight shrinkage. The knife works fine and is in EX+ condition.