90278040000 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: NUCLEAR MAGNETIC RESONANCE INSTRUMENTS, 84818091000 under HS Code Others, and 84192000000 under HS Code Others were the top imported HS Codes by MARS LABORATORY INSTRUMENTS CENTER in 2023.