If you're looking for a high-quality reverse osmosis (RO) membrane, the Dow FilmTec TW30-1812-50HR is a top contender. This Polyamide Thin-Film Composite (TFC) membrane is rated at 50 psi and purifies about 20% more water than elements rated at 60 psi, making it an efficient choice for your undersink RO system.

One of the standout features of this membrane is its long shelf life, thanks to being shipped dry. It also boasts a free chlorine tolerance of less than 0.1 ppm and is NSF/ANSI Standard 58 certified, ensuring it meets rigorous safety and performance standards.

Users have praised its ease of installation and noticeable improvement in water flow. One reviewer mentioned that after five years of use, swapping out the old cartridge was simple and resulted in much better flow. Another user appreciated the elimination of a 'funky taste' in their water, attributing it to the genuine FilmTec membrane.

Overall, the Dow FilmTec TW30-1812-50HR offers excellent value for money. It consistently lowers TDS levels and maintains them for months, making it a reliable choice over cheaper knock-offs. If you're in need of a dependable RO membrane, this product is definitely worth considering.