Formaldehyde is a gas at room temperature and one atmosphere of pressure. A saturated solution of formaldehyde in water is 37% w/w formaldehyde and this solution is properly called “formalin.” The laboratory fixative is a neutral buffered 1:10 dilution and has a formaldehyde concentration of 4% w/v. Our product with the catalog # 5738A is a 1:10 dilution of 37% formaldehyde with reagent alcohol. It is only lightly buffered because of the alcohol. The country of origin is the United States.