Roch Mechatronics Horizontal electrophoresis systems, also called submarine units, are systems designed to run agarose or polyacrylamide gels submerged in running buffer. Samples are introduced to an electric field and will migrate to the anode or cathode depending on their intrinsic charge. Systems can be used to separate DNA, RNA and proteins for quick screening applications such as sample quantification, size determination or PCR amplification detection. Systems typically come with submarine tank, casting tray, combs, electrodes and power supply. Mini, midi and maxi gel sizes are available for small, medium and large gels. System size choice will depend on sample type, size, running time and electrophoresis conditions. Pulse field gel electrophoresis systems are necessary to separate large DNA samples, greater than 15-20 Kb. Pulse field is used for genotyping, fingerprinting and epidemiological studies of pathogenic organisms. Important considerations for horizontal electrophoresis systems are sample type, buffer conditions, time and voltage needed to separate fragments, and bench top size restrictions.