According to the 2012 Handbook it’s Paraflu: “Red protective agent with antifreeze action, based on inhibited monoethyl glycol with organic formula. Exceeds CUNA NC 956-16, ASTM D 3306 specifications. FIAT Classification 9.55523.” and “cannot be mixed with any other type of fluid” and should be a “Mixture of 50% distilled water and 50% PARAFLU”
Google confirms this is indeed “based on OAT (organic acid technology).”