NDT Italiana Srl introduces portable kits for rapid testing on stainless steel and stainless steel surfaces. According to the colour taken by the paper used in the tests, it is possible to determine whether stainless steel is passive or not. The first possible test is the check of the passive state of stainless steels surfaces. Another important check that sometimes is required regards the possible presence of molybdenum so as to distinguish AISI 304 from AISI 316. An alternative testing method consists of using electrochemical reagents. With electrochemical systems, by means of a new reagent, which is sensitive to manganese, it is possible to distinguish AISI 200 series austenitic stainless steels from AISI 300 series austenitic ones.