The SB-42A is a tin dioxide semiconductor gas sensor which has a high sensitivity to HFCs (e.g. Freon: R-134a) with improved cross sensitivity to other gases.
This model is suitable for R-134a, R-410a, R-407c and other new freon family which contains R-134a. A significant feature of low power consumption design (120 mW) is advantageous for portable devices.
Gas sensitive semiconductor material is a mini bead type and a heater coil and electrode wire are embedded in the element.
The sensing element is installed in the metal housing which uses double stainless steel mesh (100 mesh) in the path of gas flow. The mesh is an anti-explosion feature