Steel Tube Rotameters are designed to work on high pressure (4000 psig) and dirty or opaque fluid applications. King has three different models of a stainless steel tube magnetically coupled designed Rotameters. They offer the low flow 65mm scale 7100 series, mid flow 7450 series and the higher flow 7710 series. The 7710 series is available with ½” up to 3” NPT or 300# flanged process connections. While the 7750 series offers all welded construction, requiring no elastomers.