ThermocoupleR-Type(S-Type) is made of high purity platinum and protected by aluminum tube of the same grade which enable it to achieve high accuracy of ±0.25%. R/S Type is capable of stable performance in vacuum, redox oxidizing gas, and metallic vapor environment. R/S Type has small thermal EMF, erroneous reading value is generally due to low grade compensation wires, which is why R/S Type are made of refined CMOCC-7N OFC and high quality constantan. Passed UL VW-1 Vertical fire test and multiple IEC tests, proven to be low smoke density, halogen free, and flame retardant.