When making PCBs (printed circuit boards), manufacturers often test the solder paste deposits using SPI (solder paste inspection). SPI systems measure the volume of the solder pads before the components are applied and the solder melted. SPI systems can reduce the incidence of solder-related defects to statistically insignificant amounts. Inline systems are manufactured by various companies such as Delvitech (Switzerland), Sinic-Tek (China), Koh Young (Korea), GOEPEL electronic (Germany), CyberOptics (US), Parmi (Korea) and Test Research, Inc. (Taiwan). Offline systems are manufactured by various companies such as by VisionMaster, Inc. (US) and Sinic-Tek (China).