What does jerome ( Vincent) place on the comb at his workstation?

In the film "Gattaca," Jerome (played by Jude Law) places a small vial of his own urine on the comb at his workstation. This action symbolizes his attempt to conceal his true genetic identity and maintain his role in the genetically stratified society. The comb serves as a tool for him to navigate the system while hiding his biological background, reflecting the themes of identity and deception in the film.