A sandwich cell consists of two (2) windows separated by a lead spacer that is amalgamated to the windows with mercury. The mercury lead amalgam is impervious to solvents and to virtually any sample. The spacer and windows form a sealed liquid sample compartment. In the case of the SL-2 configuration, the sandwich cell is also amalgamated to an aluminum front plate containing luer-lok syringe filling ports.

Sandwich cells can be used to recondition sealed cells, to have backup or supplemental sealed cells of different pathlengths, or in a demountable cell. You will find sandwich cells that will fit most sealed and demountable cell holders that have been made in the last 25 years. The SL-3 configuration uses 38.5 x 19.5 x 4mm rectangular windows, the Beckman-Specac configuration uses 41 x 23 x 6mm rectangular windows and the SL-2 & Spectra-Tech configuration uses 32 x 3mm discs. These sandwich cells can be used with any sealed or demountable cell mount with the same window sizes, regardless of who may have manufactured the cell in the mount. They are compatible with Barnes, Beckman, Buck, Mc Carthy, Perkin-Elmer, Pike, Spectra-Tech, Specac, Wilks and Wilmad cells and mounts.

As shown in Fig. 1 below, the SL-2 sandwich cell replaces the Luer syringe plate, the lead gasket, both crystals and the lead spacer. The SL-3 configuration of the sandwich cell replaces both windows and the lead spacer as shown in Fig. 2 below.

Figure 1	Figure 2