The original imported QATM single disc automatic metallographic polishing machine SAPHIR 550 from Germany is a new generation of equal diameter single disc polishing machine with Rubin 520 polishing power head. It adopts innovative polishing power head technology and has a working disc diameter of 250-300 mm. The Rubin 520 grinding and polishing power head is equipped with an automatic protective cover, which sets a new standard for safe operation. The pressure loading method of single point loading and center loading, program storage, integrated automatic liquid adding system, and accurate control of material grinding amount are only some of their functions. The electric height setting function with pneumatic clamping, combined with all other features of the host, allows the SAPHIR 520 to meet higher metallographic sample preparation requirements. It is an ideal model for metallographic laboratories such as teaching, scientific research, and quality control.