Lab Strong cartridges are comparable to the Thermos Scientific Barnstead cartridges. Side-by-side testing shows fantastic results for purity and longevity. The Lab Strong water purification cartridge is used with the Thermos Scientific Barnstead B-Pure, E-Pure, NANO pure, NANO pure II and NANO pure Quad water purification systems. The water purification cartridge provides outstanding quality you expect from your water system at a low cost. The cartridge is an economical alternative for all laboratories. The cartridge life capacity is indicated by resin color change. The water purification cartridge provides outstanding quality you expect from your water system at a low cost. The cartridge is an economical alternative for all laboratories and is ideal for small volume applications. Lab Strong takes extra care in sealing our water purification cartridges multiple ways, ensuring exceptional quality is maintained throughout the two year shelf life. Each cartridge has fitted sealing plugs/caps placed on both ends and then it is further sealed in a bag ? the combination of which dramatically inhibits drying out of the resin.