38220090000 under HS Code DIAGNOSTIC OR LABORATORY REAGENTS ON A BACKING, PREPARED DIAGNOSTIC OR LABORATORY REAGENTS WHETHER OR NOT ON A BACKING, OTHER THAN THOSE OF HEADING 3002 OR 3006; CERTIFIED REFERENCE MATERIALS DIAGNOSTIC OR LABORATORY REAGENTS ON A BACKING, PREPARED DIAGNOSTIC OR LABORATORY REAGENTS WHETHER OR NOT ON A BACKING, OTHER THAN THOSE OF HEADING 3002 OR 3006; CERTIFIED REFERENCE MATERIALS: OTHER, 90278030000 under HS Code INSTRUMENTS AND APPARATUS FOR PHYSICAL OR CHEMICAL ANALYSIS (FOR EXAMPLE, POLARIMETERS, REFRACTOMETERS, SPECTROMETERS, GAS OR SMOKE ANALYSIS APPARATUS); INSTRUMENTS AND APPARATUS FOR MEASURING OR CHECKING VISCOSITY, POROSITY, EXPANSION, SURFACE TENSION OR THE LIKE; INSTRUMENTS AND APPARATUS FOR MEASURING OR CHECKING QUANTITIES OF HEAT, SOUND OR LIGHT (INCLUDING EXPOSURE METERS); MICROTOMES - OTHER INSTRUMENTS AND APPARATUS: INSTRUMENTS AND APPARATUS FOR MEASURING THE SURFACE OR INTERFOCIAL TENSION OF LIQUIDS, and 90279099000 under HS Code Others were the top imported HS Codes by SERVE DIAGNOSTICA INC in 2023.