Potassium 4,5,6,7-tetrabromo-3'-hydroxy-3-oxo-3H-spiro[isobenzofuran-1,9'-xanthen]-6'-olate(2:1) 5g

Potassium 4,5,6,7-tetrabromo-3'-hydroxy-3-oxo-3H-spiro[isobenzofuran-1,9'-xanthen]-6'-olate(2:1) 5g