high quality molecular sieve 1)10 years professional manufacturer for 3A, 4A,5A, 13X 2)drying,absorbent,cleaning ect. producthigh quality ... high vacuum.3A (pore size 3 Å): Adsorbs NH3, H2O, (not C2H6), good for drying polar liquids.4A (pore size 4 ... for removal of thioalcohol in aviation kerosen and the liquid hydrocarbon Package can meet individrual requirements high quality molecular sieve