GB/535-1995 Classification Standard for Ammonium Sulfate Posted on 2024-08-18 13:02:46   Exterior Nitrogen content% Free acid content% Moisture% First grade No visible mechanical impurities ≥ 21.0 ≤ 0.05 ≤ 0.3 Rxiry ED Binocularsprecise,accurate,binoculars,outtingRxiry (Jiangsu) Optoelectronic Co., Ltd , https://www.rxiryrangefinder.com