"MATERIAL IS COPPER ALLOY, MATERIAL SPEC QQ-B-639 ALY 464 HALF HARD; MANIFOLD HAS SIXTEEN 0.438-20UNC-2B LINE CONNECTION HOLES COUNTER SUNK 0.073-0.088; A TOTAL OF FOUR AIR PASSAGES 0.250 IN. DIA RUN THRU THE WIDTH; FOUR MOUNTING HOLES 0.281 IN. DIA; MANIFOLD IS 7.56 IN. LONG X 4.00 IN. WIDE X 1.25 IN. THICK; NHA SPECIAL ALARM CONNECTION BOX."