The 1073823 replacement gas cell O-ring, is a 2-013 Viton O-ring incorporated into MultiGas 203X/603x Fourier Transform Infrared (FTIR) gas analyzers having a gas cell volume of 70mL. Situated between the cell window retainers and themal spacer, these orings serve to isolate the internals of the detector optical box compartment from the external environment. As part of routine gas cell maintenance, 1073823 orings should be replaced upon becoming brittle, damaged or lost. Quantity of one 1073823 o-ring included (Two 1073823 o-rings required for full replacement)