Seracult Single Slide Fecal Occult Blood Test 371001 (37100100). The Seracult FOBT guaiac test is a qualitative aid in the diagnosis of colorectal cancer. It is designed for use in routine physical examinations in doctors' offices, hospitals, clinics and laboratories. One box contains 100 slides, two 15mL bottles of developer and 100 applicators. Priced per box.