AK20I means 80% nitric acid + 20% N2O4 + Iodine passivant
AK = Azotna Kislota = Nitric Acid in
NASA
Similar to AK20I
2IC - Second In Command
2M - Micro Miniature
2MASS - Two Micron All-Sky Survey
2STO - Two Stage To Orbit
3-DOF - Three Degree Of Freedom
3AAL - Three Axis Acoustic Levitator
6-DOF - Six Degree Of Freedom
View all in NASA