BA6: BLACK ARMORHIDE TYPE 6 : "SURVIVAL"; POWDER COATED; 440C STEEL; STRAIGHT; 8 TEETH/IN.; BRUSH FINISH BLADE; VERTICAL 1 & 2 LOGOS; "MARK IIT" ETCHED ON BLADE
The BA6 knives are identical to the BA4 knives but have "MARK IIT" electro-etched on the blade logo side, on the upper flat of the blade when the knife point is on the left. Most are centered in the serration area, however on some early BA6 knives the electro-etch is found lower towards the handle. I don't know why the marking was added but may have been the result of a spate of Mark II copies that hit the knife market.
The BA6 knives are found on mid 1985 to late 1998 knives in the approximate serial range of D0314S - N4082S