In the year of 1988, Hey-Wel Mechanical Ltd. was founded as a specialist manufacturer for Metering Pumps and 3-lobes Roots Blowers, and RS-type series had reached to our maturity stage after years of modifications and testing in year of 1991. In the same year, Hey-Wel decided to quit the metering pump line, and transformed to be a real specialist of the 3-lobes Roots Blowers. However, this stage is not a stage for Hey-Wel to stop developing, it was a beginning instead. We concentrated in the development of new types, RSS and RSW types were born with beliefs. RSS type is excellent at performing at high rpm and high pressure working, and in order to compensate the shortage of the RSS type at the pressure range that exceeds 0.8 kgf/cm², RSW type was developed. With efforts of our staffs and by constant investment, now we are able to produce parts which are totally meet with our design, and in the mean while, can also deliver goods to our clients within promised date, and to offer our clients the best, fast and efficient service. Seeking for the best performance is what we always insist, we will keep on modifying our products to supply efficient and reliable products to our clients.