LC-20AB Binary Solvent Delivery Unit is a binary high-pressure gradient solvent delivery device that combines two LC-20AD pumps into a compact device. The space-saving design and excellent performance of the LC-20AD pump offer an accurate high-pressure gradient. By adding a new type of check valve and modifying the solvent delivery control method, the flow accuracy and precision in the micro-flow area are improved. Non-polar organic solvents (such as hexane) can be stably transported.