The RM Foil Stamp Set ME: 30384986 pushes samples such as foils, granulates or gums flat on the prism of the RM40 refractometers and ensures full contact of the sample with the refractive index cell during measurements. With this technique of pressing the sample on to prism contact liquid is no longer needed to ensure that there is no air gap between the sample and the prism. This application note covers the approached with the foil stamp, using foils and granulates in the determination of bound styrene in styrene-butadiene rubber (SBR). The ASTM D5775 provides a norm which describes all necessary steps for sample preparation, measurement with an Abbe refractometer and calculation of the bound styrene content. Our foil stamp approach, although it does not fulfill all the requirements of the ASTM D5775 norm, can be regarded as a good alternative for measuring such samples.